Function to generate random strings of a given length containing characters from a given set

randomStringFromCharacterSet.php

<?php
	function randomStringFromCharacterSet($length, $possibleCharacters){
		return substr(str_shuffle(str_repeat($possibleCharacters,$length)),0,$length);
	}
	
	//Example of usage
	$possibleCharacters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
	$length = 5;
	for($i=0;$i<10;$i++){
		echo randomStringFromCharacterSet($length, $possibleCharacters).'</br>';
	}
?>