How to hash a string to integer with a range in PHP

Here is a simple way in PHP to hash a string to an integer. That is, mapping a string to a specific number.

function str_hash($str, $range=100){

$number = crc32($str);

return $number % $range;

}

This function has a default range of 100. (That means the outcome can be 0 – 99 )

Simple load-balancing depends on the username

$servers = array('10.0.0.1', '10.0.0.2', '10.0.0.3');

$serverIndex = str_hash($username, 3);

$link = processDownload($servers[$serverIndex], $fileId);

header('Location: ' . $link);

1. This stackoverflow post is related to how to hash a string to integer using md5, but I found the resulting integer is too large for my practical use
http://stackoverflow.com/questions/965304/php-hash-form-string-to-integer