PHP - highlight_string & highlight_file

Ever noticed that one some of the webmasters city's or script places they have a nice colored output from their codes. But how do they do that ? Simple ! Since PHP 4 you can 'Highlight' a code. This means the code won't be executed but that it will be printed out on a page with pre-defined colors !

To make everything easier PHP has 2 different highlights. A highlight_string and a highlight_file. The difference between those 2 is that highlight_string will only highlight the inserted string so you can code around it. Hightlight file can only output a full file. So when you are going to show the people a bit of your code you use highlight_string put if you want to output a full page code you use highlight_file.

Example 1 : Highlight_string :

<?php
highlight_string("
<?php
echo 'hello';
?>
");
?>

Will output :

<?php
echo 'hello';
?>


Example 2 : Highlight_file :

<?php
echo "<b><u>Test.php :</b></u><br>";
highlight_file("test.php");
?>

and test.php contains :

<?php
echo "test";
?>

Will output :

Test.php :

<?php
echo "test";
?>

It looks the same but with highlight_file you can do a much faster work if you have a script from some pages !
Like when you have a directory full with precious php files that you want to share. Then you can just use this code (php.net + some own edits to prevent people to read other dir's) :

<?php
$file = preg_replace('.', '', $_GET['file']);
if (!isset($file) || trim($file) == '') {
    echo 'please pass me something yummy';
    die(0);
}

if (!file_exists($file).'.php') {
    echo '<b>'.$file.'.php</b> does not seem to exist :(';
    die(0);
}

highlight_file($file.'.php');
?>

So file.php?file=test will return

<?php
echo "test";
?>