Generate a string of random characters

randomString.php

function generateRandomString($length = 10)
{
    $alphabet = '0123456789abcdefghijklmnopqrstuvwxyz';
    $alphabet_length = strlen($alphabet);

    $randomChars = array();
    for ($i = 0; $i < $length; $i++)
    {
        $randomChars[] = $alphabet[mt_rand(0, $alphabet_length - 1)];
    }
    return join('', $randomChars);
}