PHP实现过滤掉非汉字字符只保留中文字符

<?php $str = "a 1b 2b。xxyy字符"; //转换 GB2312 -> UTF-8 $str = mb_convert_encoding($str, 'UTF-8', 'GB2312'); preg_match_all('/[\x{4e00}-\x{9fff}]+/u', $str, $matches); $str = join('', $matches[0]); //转换 UTF-8 -> GB2312 $str = mb_convert_encoding($str, 'GB2312', 'UTF-8'); echo $str; //输出 中文字符 ?&g