截取字符串 php截断字符串

php;toolbar:false;">function htmlencode($string) {
    if(is_array($string)) {
        foreach($string as $key => $val) {
            $string[$key] = htmlencode($val);
        }
    } else {
        $string = preg_replace('/&amp;((#(\d{3,5}|x[a-fA-F0-9]{4})|[a-zA-Z][a-z0-9]{2,5});)/', '&\\1', str_replace(array('&', '"', '<', '>'), array('&amp;', '"', '<', '>'), $string));
    }
    return $string;
}

function cutStr($string, $length = 0, $dot = '') {
    $string = strip_tags($string);
    $string = trim($string);
    $string = str_replace(array('&amp;', '"', '<', '>'), array('&', '"', '<', '>'), $string);
    $strlen = strlen(phpcharset($string, 'GBK'));
    $charset = mb_detect_encoding($string, array('ASCII', 'UTF-8', 'GBK', 'GB2312', 'BIG5'));
    if($length && ($strlen > $length)) {
        $wordscut = '';
        if(strtolower($charset) == 'utf-8') {
            $n = 0;
            $tn = 0;
            $noc = 0;
            while($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;
            }
            $wordscut = substr($string, 0, $n);
        } else {
            for($i = 0; $i < $length - 1; $i++) {
                if(ord($string[$i]) > 127) {
                    $wordscut .= $string[$i].$string[$i + 1];
                    $i++;
                } else {
                    $wordscut .= $string[$i];
                }
            }
        }
        $wordscut .= $dot;
        $string = $wordscut;
    }
    return htmlencode($string);
}