PHP subistr 截取字符串无码

更新时间：20120102

[PHP]代码

<?php

/**
 *      [WebodMin] (C)2010-2099 Blank Inc.
 *      This is NOT a freeware, use is subject to license terms
 *
**/

function subistr($string, $length, $dot = ' ...') { 
    global $charset; 
    if(strlen($string) <= $length) { 
        return $string; 
    } 
    $s = ''; 
    if(strtolower($charset) == 'utf-8') { 
        $n = $tn = $noc = 0; 
        while($n < strlen($string)) { 
            $t = ord($string[$n]); 
            if($t == 9 || $t == 10 || (32 <= $t && $t <= 126)) { 
                $tn = 1; $n++; $noc++; 
            } elseif(194 <= $t && $t <= 223) { 
                $tn = 2; $n += 2; $noc += 2; 
            } elseif(224 <= $t && $t <= 239) { 
                $tn = 3; $n += 3; $noc += 2; 
            } elseif(240 <= $t && $t <= 247) { 
                $tn = 4; $n += 4; $noc += 2; 
            } elseif(248 <= $t && $t <= 251) { 
                $tn = 5; $n += 5; $noc += 2; 
            } elseif($t == 252 || $t == 253) { 
                $tn = 6; $n += 6; $noc += 2; 
            } else { 
                $n++; 
            } 
            if($noc >= $length) { 
                break; 
            } 
        } 
        if($noc > $length) { 
            $n -= $tn; 
        } 
        $s = substr($string, 0, $n); 
    } else { 
        for($i = 0; $i < $length; $i++) { 
            $s .= ord($string[$i]) >= 127 ? $string[$i].$string[++$i] : $string[$i]; 
        } 
    }
    return $s.$dot; 
}