php - UTF-8 all the way through

106

I'm setting up a new server and want to support UTF-8 fully in my web application. I have tried this in the past on existing servers and always seem to end up having to fall back to ISO-8859-1.

Where exactly do I need to set the encoding/charsets? I'm aware that I need to configure Apache, MySQL, and PHP to do this — is there some standard checklist I can follow, or perhaps troubleshoot where the mismatches occur?

This is for a new Linux server, running MySQL 5, PHP, 5 and Apache 2.

793

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

219

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

546

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

342

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
204

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

452

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
751

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

764

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

81

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

879

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

740

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

604

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

782

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

295

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

788

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

832

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

712

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
780

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

91

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
44

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

908

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

983

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

562

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

951

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

321

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

821

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

705

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

942

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

951

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

552

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
325

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

956

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
288

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

852

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

733

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

148

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

677

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

587

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

26

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

339

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

925

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

324

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

80

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
485

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

618

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
888

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

287

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

566

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

227

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

300

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

833

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

518

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

457

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

585

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

707

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

814

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
731

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

279

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
420

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

328

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

62

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

896

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

795

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

627

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

934

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

992

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

783

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

96

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

798

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
389

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

801

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
323

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

503

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

203

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

968

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

278

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

731

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

844

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

491

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

264

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

889

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

883

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
681

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

939

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
790

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

333

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

727

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

808

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

924

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

316

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

942

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

228

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

870

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

576

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

162

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
600

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

104

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
89

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

133

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

82

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

76

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

512

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

261

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

32

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

620

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

7

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

513

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

535

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
277

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

585

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
364

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

207

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

990

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

905

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

649

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

561

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

460

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

525

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

632

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

874

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

185

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
281

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

821

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
141

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

431

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

524

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

452

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

140

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

762

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

310

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

576

Answer

Solution:

Data Storage:

  • Specify theutf8mb4 character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly useutf8mb4 encoding if autf8mb4_* collation is specified (without any explicit character set).

  • In older versions of MySQL (< 5.5.3), you'll unfortunately be forced to use simplyutf8, which only supports a subset of Unicode characters. I wish I were kidding.

Data Access:

Output:

Input:

Other Code Considerations:

726

Answer

Solution:

I'd like to add one thing to chazomaticus' excellent answer:

Don't forget the META tag either (like this, or the HTML4 or XHTML version of it):

<meta charset="utf-8">

That seems trivial, but IE7 has given me problems with that before.

I was doing everything right; the database, database connection and Content-Type HTTP header were all set to UTF-8, and it worked fine in all other browsers, but Internet Explorer still insisted on using the "Western European" encoding.

It turned out the page was missing the META tag. Adding that solved the problem.

Edit:

The W3C actually has a rather large section dedicated to I18N. They have a number of articles related to this issue – describing the HTTP, (X)HTML and CSS side of things:

They recommend using both the HTTP header and HTML meta tag (or XML declaration in case of XHTML served as XML).

606

Answer

Solution:

In addition to settingdefault_charset in php.ini, you can send the correct charset usingheader() from within your code, before any output:

header('Content-Type: text/html; charset=utf-8');

Working with Unicode in PHP is easy as long as you realize that most of the string functions don't work with Unicode, and some might mangle strings completely. PHP considers "characters" to be 1 byte long. Sometimes this is okay (for example, explode() only looks for a byte sequence and uses it as a separator -- so it doesn't matter what actual characters you look for). But other times, when the function is actually designed to work on characters, PHP has no idea that your text has multi-byte characters that are found with Unicode.

A good library to check into is phputf8. This rewrites all of the "bad" functions so you can safely work on UTF8 strings. There are extensions like the mb_string extension that try to do this for you, too, but I prefer using the library because it's more portable (but I write mass-market products, so that's important for me). But phputf8 can use mb_string behind the scenes, anyway, to increase performance.

189

Answer

Solution:

Warning: This answer applies to PHP 5.3.5 and lower. Do not use it for PHP version 5.3.6 (released in March 2011) or later.

Compare with Palec's answer to .


I found an issue with someone using PDO and the answer was to use this for the PDO connection string:

$pdo = new PDO(
    'mysql:host=mysql.example.com;dbname=example_db',
    "username",
    "password",
    array(PDO::MYSQL_ATTR_INIT_COMMAND => "SET NAMES utf8"));
754

Answer

Solution:

In my case, I was usingmb_split, which uses regular expressions. Therefore I also had to manually make sure the regular expression encoding was UTF-8 by doingmb_regex_encoding('UTF-8');

As a side note, I also discovered by runningmb_internal_encoding() that the internal encoding wasn't UTF-8, and I changed that by runningmb_internal_encoding("UTF-8");.

16

Answer

Solution:

First of all, if you are in PHP before 5.3 then no. You've got a ton of problems to tackle.

I am surprised that none has mentioned the library, the one that has good support for Unicode, graphemes, string operations, localisation and many more, see below.

I will quote some information about Unicode support in PHP by Elizabeth Smith's slides at PHPBenelux'14

INTL

Good:

  • Wrapper around ICU library
  • Standardised locales, set locale per script
  • Number formatting
  • Currency formatting
  • Message formatting (replaces gettext)
  • Calendars, dates, time zone and time
  • Transliterator
  • Spoofchecker
  • Resource bundles
  • Convertors
  • IDN support
  • Graphemes
  • Collation
  • Iterators

Bad:

  • Does not support zend_multibyte
  • Does not support HTTP input output conversion
  • Does not support function overloading

mb_string

  • Enables zend_multibyte support
  • Supports transparent HTTP in/out encoding
  • Provides some wrappers for functionality such as strtoupper

ICONV

  • Primary for charset conversion
  • Output buffer handler
  • mime encoding functionality
  • conversion
  • some string helpers (len, substr, strpos, strrpos)
  • Stream Filterstream_filter_append($fp, 'convert.iconv.ISO-2022-JP/EUC-JP')

DATABASES

  • MySQL: Charset and collation on tables and on the connection (not the collation). Also, don't use mysql - mysqli or PDO
  • postgresql: pg_set_client_encoding
  • sqlite(3): Make sure it was compiled with Unicode and intl support

Some other gotchas

  • You cannot use Unicode filenames with PHP and windows unless you use a 3rd part extension.
  • Send everything in ASCII if you are using exec, proc_open and other command line calls
  • Plain text is not plain text, files have encodings
  • You can convert files on the fly with the iconv filter
236

Answer

Solution:

The only thing I would add to these amazing answers is to emphasize on saving your files in UTF-8 encoding, I have noticed that browsers accept this property over setting UTF-8 as your code encoding. Any decent text editor will show you this. For example, Notepad++ has a menu option for file encoding, and it shows you the current encoding and enables you to change it. For all my PHP files I use UTF-8 without a BOM.

Sometime ago I had someone ask me to add UTF-8 support for a PHP and MySQL application designed by someone else. I noticed that all files were encoded in ANSI, so I had to use iconv to convert all files, change the database tables to use the UTF-8 character set and utf8_general_ci collate, add 'SET NAMES utf8' to the database abstraction layer after the connection (if using 5.3.6 or earlier. Otherwise, you have to use charset=utf8 in the connection string) and change string functions to use the PHP multibyte string functions equivalent.

816

Answer

Solution:

I recently discovered that usingstrtolower() can cause issues where the data is truncated after a special character.

The solution was to use

mb_strtolower($string, 'UTF-8');

mb_ uses MultiByte. It supports more characters but in general is a little slower.

484

Answer

Solution:

In PHP, you'll need to either use the multibyte functions, or turn on mbstring.func_overload. That way things like strlen will work if you have characters that take more than one byte.

You'll also need to identify the character set of your responses. You can either use AddDefaultCharset, as above, or write PHP code that returns the header. (Or you can add a META tag to your HTML documents.)

779

Answer

Solution:

I have just gone through the same issue and found a good solution at PHP manuals.

I changed all my files' encoding to UTF8 and then the default encoding on my connection. This solved all the problems.

if (!$mysqli->set_charset("utf8")) {
    printf("Error loading character set utf8: %s\n", $mysqli->error);
} else {
   printf("Current character set: %s\n", $mysqli->character_set_name());
}

View Source

879

Answer

Solution:

Unicode support in PHP is still a huge mess. While it's capable of converting an ISO 8859 string (which it uses internally) to UTF-8, it lacks the capability to work with Unicode strings natively, which means all the string processing functions will mangle and corrupt your strings.

So you have to either use a separate library for proper UTF-8 support, or rewrite all the string handling functions yourself.

The easy part is just specifying the charset in HTTP headers and in the database and such, but none of that matters if your PHP code doesn't output valid UTF-8. That's the hard part, and PHP gives you virtually no help there. (I think PHP 6 is supposed to fix the worst of this, but that's still a while away.)

159

Answer

Solution:

If you want a MySQL server to decide the character set, and not PHP as a client (old behaviour; preferred, in my opinion), try addingskip-character-set-client-handshake to yourmy.cnf, under[mysqld], and restartmysql.

This may cause trouble in case you're using anything other than UTF-8.

133

Answer

Solution:

The top answer is excellent. Here is what I had to on a regular Debian, PHP, and MySQL setup:

// Storage
// Debian. Apparently already UTF-8

// Retrieval
// The MySQL database was stored in UTF-8,
// but apparently PHP was requesting ISO 8859-1. This worked:
// ***notice "utf8", without dash, this is a MySQL encoding***
mysql_set_charset('utf8');

// Delivery
// File *php.ini* did not have a default charset,
// (it was commented out, shared host) and
// no HTTP encoding was specified in the Apache headers.
// This made Apache send out a UTF-8 header
// (and perhaps made PHP actually send out UTF-8)
// ***notice "utf-8", with dash, this is a php encoding***
ini_set('default_charset','utf-8');

// Submission
// This worked in all major browsers once Apache
// was sending out the UTF-8 header. I didn’t add
// the accept-charset attribute.

// Processing
// Changed a few commands in PHP, like substr(),
// to mb_substr()

That was all!

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