crop.php

<?php

function utfcrop($string, $bytecount)
{
    $ret = "";
    $len = strlen($string);
    for ($i = 0; $i < $len; $i++) {
        if (($string[$i] & 0x80) == 0 && $i + 1 > $bytecount)
            return $ret;
        else if (($string[$i] & 0xE0) == 0xD0 && $i + 2 > $bytecount)
            return $ret;
        else if (($string[$i] & 0xF0) == 0xE0 && $i + 3 > $bytecount)
            return $ret;
        else if (($string[$i] & 0xF8) == 0xF0 && $i + 4 > $bytecount)
            return $ret;
        else 
            $ret .= $string[$i];
    }
    return $ret;
}