If you want to allow repetitive occurences of characters, you can use this function:
function randString($length, $charset="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789")
{
$str="";
$count = strlen($charset);
while ($length--) {
$str .= $charset[mt_rand(0, $count-1)];
}
return $str;
}
The basic algorithm is to generate <length> times a random number between 0 and <number of characters> â 1 we use as index to pick a character from our set and concatenate those characters. The 0 and <number of characters> â 1 bounds represent the bounds of the $charset
string as the first character is addressed with $charset[0]
and the last with $charset[count($charset) - 1]
.