function generateRandomString($length = 10) {
$characters = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
$randomString = '';
for ($i = 0; $i < $length; $i++) {
$randomString .= $characters[rand(0, strlen($characters) - 1)];
}
return $randomString;
}
function getRandomString($length = 6)
{
$validCharacters = "abcdefghijklmnopqrstuxyvwzABCDEFGHIJKLMNOPQRSTUXYVWZ+-*#&@!?";
$validCharNumber = strlen($validCharacters);
$result = "";
for ($i = 0; $i < $length; $i++) {
$index = mt_rand(0, $validCharNumber - 1);
$result .= $validCharacters[$index];
}
return $result;
}
http://www.phpf1.com/tutorial/generate-random-string.html