- str_split: documentation ( source)
<?php
$num = 999999999;
$return = '';
$result_62 = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ';
$result_62_arr = str_split($result_62);
while($num != 0) {
// $return = $result_62_arr[bcmod($num,62)].$return;
// $num = bcdiv($num,62,0);
$return = $result_62_arr[(intval($num)%62)].$return;
$num = $num/62;
}
echo $return;