thinkphp3.2模板截取字符串函数

function msubstr($str, $start=0, $length, $charset="utf-8", $suffix=true)  

{  

    if(function_exists("mb_substr")){  
    
        if($suffix)  
        
              return mb_substr($str, $start, $length, $charset)."...";  
              
        else
        
             return mb_substr($str, $start, $length, $charset);  
             
        }  
        
        elseif(function_exists('iconv_substr')) {  
        
            if($suffix)  
            
                return iconv_substr($str,$start,$length,$charset)."...";  
                
            else
            
                return iconv_substr($str,$start,$length,$charset);  
                
         }  

         $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));  

         if($suffix) return $slice."…";  

         return $slice;

    }