php - How to make and call a function if it has a loop inside of it?

560

I have a for loop that displays all of the images inside of an array. How can I put that inside of a function, so when I need it I can call it and it will show all of the pictures?

$countArray = count($fil[0]);

function displayAllImages(){
for ($x=0; $x<$countArray; $x++){
    echo '<img src="photos/'.$fil[0][$x].'" /><br />';
}
}
displayAllImages(); //nothing shows up

Answer

Solution:

Since you declared $fil and $countArray outside the function, you have no access to them, so you should pass the array as a function argument

function displayAllImages($images){
  $counter = count($images[0]);
  for ($x=0; $x < $counter; $x++){
      echo '<img src="photos/'.$images[0][$x].'" /><br />';
  }
}
displayAllImages($countArray, $fil); //now it will show up

The best way to do such a thing would probably be the following using the foreach loop:

function displayAllImages($imagesSources){
  foreach($imagesSources as $value){
    echo '<img src="photos/'.$value.'" /><br />';
  }
}

$images = array("image1.png", "image2.png", "image3.png");
displayAllImages($images);

$images = array("0" => array("image1.png", "image2.png", "image3.png"));
//in this case you can pass directly $images[0] to the function as pointed in the comments
displayAllImages($images[0]);

and as pointed in the comments have a look at php variable scope HERE

999

Answer

Solution:

the reason is, that you use a variabe inside a function, that is not declared activate error_reporting, and PHP should note, that $countArray isn't declared.

2 possibilities:

giving the functino the Array as a Parameter:

// $fil[0] is an array

function displayAllImages($a)
{
    if(is_array($a)) foreach($a as $i => $v)
    {
        echo '<img src="photos/'.$v.'" /><br />';
    }
}
displayAllImages($fil[0]);

or you tell PHP inside the function, that you want to use a variable outside the function:

// $fil[0] is an array

function displayAllImages()
{
    global $fil;
    if(is_array($fil[0])) foreach($fil[0] as $i => $v)
    {
        echo '<img src="photos/'.$v.'" /><br />';
    }
}
displayAllImages();

please look at http://php.net/manual/en/language.variables.scope.php

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