<?php
header("Content-type:text/html; charset=utf-8"); 

/*
mb_substr( $str, $start, $length, $encoding ) 

$str，需要截断的字符串 
$start，截断开始处，起始处为0 
$length，要截取的字数 
$encoding，网页编码，如utf-8,GB2312,GBK


mb_strlen( $str, $encoding ) 

$str，要计算长度的字符串 
$encoding，网页编码，如utf-8,GB2312,GBK 


 */




?>