<script>

function subString(str, len, hasDot)

{

var newLength = 0;

var newStr = "";

var chineseRegex = /[^\x00-\xff]/g;

var singleChar = "";

var strLength = str.replace(chineseRegex,"**").length;

for(var i = 0;i < strLength;i++){

singleChar = str.charAt(i).toString();

if(singleChar.match(chineseRegex) != null){

newLength += 2;

}else{

newLength++;

}

if(newLength > len){

break;

}

newStr += singleChar;

}

if(hasDot && strLength > len){

newStr += "...";

}

return newStr;

}

alert(subString("js擷取中英文字串無亂碼",10,true));

</script>