split string after x characters

Solution 1:

If you need to split a string after every 5 characters, try str_split():

$output = str_split($string, 5);

If you only need to extract the first 5 characters and put the rest of the string in the second part of your array, you can use substr() as NullUserException suggests (code from his now-deleted answer):

$output[0] = substr($string, 0, 5);
$output[1] = substr($string, 5);

Solution 2:

With the help of BoltClocks' answer I have created the following function to solve the problem:

function split_on($string, $num) {
    $length = strlen($string);
    $output[0] = substr($string, 0, $num);
    $output[1] = substr($string, $num, $length );
    return $output;
}