DZX1.5字符串截断函数cutstr分享

<?php 
/**
 * 函数来源DZX1.5，文件所在 /source/function/function_core.php
 */
define('CHARSET','UTF-8');

function cutstr($string, $length, $dot="...") {
	if(strlen($string)<=$length) {
		return $string;
	}
	
	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 = $length) {
				break;
			}
		}
		if($noc > $length) {
			$n -= $tn;
		}
		$strcut = substr($string, 0, $n);
	} else {
		for($i = 0; $i < $length; $i++) {
			$strcut .= ord($string[$i])>127 ? $string[$i].$string[++$i] : $string[$i];
		}
	}
	
	$pos = strrpos($strcut, chr(1));
	if($pos !== false) {
		$strcut = substr($strcut,0,$pos);
	}
	
	return $strcut.$dot;
}

$string = '测试数据库ablci102020@(#)!)!测试劳动力ddk';
echo cutstr($string,15);
/*End of php*/