String Random

stringRandom.php

/**
 * @param int $size
 * @return string
 */
public function stringRandom($size) {
    $validCharacters = utf8_decode("abcdefghijklmnopqrstuvxwzABCDFGHIJKLMNOPQRSTUVXWZ");
    $validCharNumber = strlen($validCharacters);
    $string = '';
    while (strlen($string) < $size) {
        $index = mt_rand(0, $validCharNumber - 1);
        $string .= $validCharacters[$index];
    }
    return $string;
}