字符截取,解决中文的截取问题

 1       public function  cutStr($string,  $start ,$sublen, $extstring='', $code = 'UTF-8')    
 2   {
 3       if ($code == 'UTF-8'
 4       {
 5           $pa = "/[\x01-\x7f]|[\xc2-\xdf][\x80-\xbf]|\xe0[\xa0-\xbf][\x80-\xbf]|[\xe1-\xef][\x80-\xbf][\x80-\xbf]|\xf0[\x90-\xbf][\x80-\xbf]

                          [\x80-\xbf]|[\xf1-\xf7][\x80-\xbf][\x80-\xbf][\x80-\xbf]/"
 6           preg_match_all($pa, $string, $t_string); 
 7           if(count($t_string[0]) - $start > $sublen
 8             return join('', array_slice($t_string[0], $start, $sublen)).$extstring
 9             return join('', array_slice($t_string[0], $start, $sublen)); 
10       } else { 
11           $start = $start*2
12           $sublen = $sublen*2
13           $strlen = strlen($string); 
14           $tmpstr = ''
15           for($i=0$i<$strlen$i++
16           { 
17               if($i>=$start && $i<($start+$sublen)) 
18               { 
19                   if(ord(substr($string, $i, 1))>129
20                   {
21                       $tmpstr.= substr($string, $i, 2); 
22                   } else { 
23                       $tmpstr.= substr($string, $i, 1); 
24                   } 
25               } 
26               if(ord(substr($string, $i, 1))>129$i++
27           } 
28           if(strlen($tmpstr)<$strlen ) $tmpstr.= $extstring
29           return $tmpstr
30       } 
31   } 

原文地址:https://www.cnblogs.com/buffer/p/1877324.html