Online PHP editor | refs for 6S8UW

<?php function c_substr($string, $from, $length = null){ preg_match_all('/[x80-xff]?./', $string, $match); if(is_null($length)){ $result = implode('', array_slice($match[0], $from)); }else{ $result = implode('', array_slice($match[0], $from, $length)); } return $result; } $str = "zhon华人min共和guo"; $from = 3; $length = 7; echo(c_substr($str, $from, $length));