JS截字符串处理数字，汉字，英文问题

<script>
function suolve( str,sub_length ){
var temp1 = str.replace(/[^\x00-\xff]/g,"**");//精髓
var temp2 = temp1.substring(0,sub_length);
//找出有多少个*
var x_length = temp2.split("\*").length - 1 ;
var hanzi_num = x_length /2 ;
sub_length = sub_length - hanzi_num ;//实际需要sub的长度是总长度-汉字长度
var res = str.substring(0,sub_length);
if(sub_length < str.length ){
var end =res+"……" ;
}else{
var end = res ;
}
return end ;
}
var str1="1111哇咔咔咔";
var str2="11哇11哇咔咔咔"
console.log(suolve(str1,6));
console.log(suolve(str2,6));
</script>