PHP only keeps Chinese characters alphanumeric

This article mainly introduces the PHP is only reserved Chinese characters alphanumeric, has a certain reference value, now share to everyone, have the need for friends can refer to

PHP only keeps Chinese characters alphanumeric

All Chinese and english symbols $str = "><? "\" "Hello Feed 555?" "|" : l}{p+_) in Thsdff0?><m<>\ "s~!@#$%^&* () +_) (*&dsdffsde~! @#￥%......&*5545445 () +--) (*&......%￥#@! ~ The movie _ The day after 230809-peopl.e die i d. (*&^%$#@!! ~ "; echo Match_chinese ($STR); function Match_chinese ($chars, $encoding = ' utf8 ') {    $pattern = ($encoding = = ' UTF8 ')? ' /[\x{4e00}-\x{9fa5}a-za-z0-9]/u ': '/[\x80-\xff]/';    Preg_match_all ($pattern, $chars, $result);    $temp =join (", $result [0]);    return $temp;}