/**  * 字符串截取，支持中文和其他编码  * @static  * @access public  * @param string $str 需要转换的字符串  * @param string $start 开始位置  * @param string $length 截取长度  * @param string $charset 编码格式  * @param string $suffix 截断显示字符  * @return string  */ function msubstr($str, $start=0, $length, $charset="utf-8", $suffix=true) {     if(function_exists("mb_substr"))         $slice = mb_substr($str, $start, $length, $charset);     elseif(function_exists('iconv_substr')) {         $slice = iconv_substr($str,$start,$length,$charset);         if(false === $slice) {             $slice = '';         }     }else{         $re['utf-8']   = "/[x01-x7f]|[xc2-xdf][x80-xbf]|[xe0-xef][x80-xbf]{2}|[xf0-xff][x80-xbf]{3}/";         $re['gb2312'] = "/[x01-x7f]|[xb0-xf7][xa0-xfe]/";         $re['gbk']    = "/[x01-x7f]|[x81-xfe][x40-xfe]/";         $re['big5']   = "/[x01-x7f]|[x81-xfe]([x40-x7e]|xa1-xfe])/";         preg_match_all($re[$charset], $str, $match);         $slice = join("",array_slice($match[0], $start, $length));     }     return $suffix ? $slice.'...' : $slice; }