js将中文转换为unicode编码

var columns = [{
            "data": "name",
            "title": "张三"
        }, {
            "data": "sex",
            "title": "男"
        }, {
            "data": "class",
            "title": "二年三班"
        }]

function toUnicode (arr){
            
        var strArr=[];
        for(var i = 0;i<arr.length;i++){
            strArr.push(arr[i].title);
        }
        var str = strArr.join(',');    
function isChinese(s){
    return /[\u4e00-\u9fa5]/.test(s);
}    
function ch2Unicdoe(str){
    if(!str){
        return;
    }
    var unicode = '';
    for (var i = 0; i <  str.length; i++) {
        var temp = str.charAt(i);
        if(isChinese(temp)){
            unicode += '\\u' +  temp.charCodeAt(0).toString(16);
        }
        else{
            unicode += temp;
        }
    }
    return unicode;
    }    
var aa = ch2Unicdoe(str); 
var bb = aa.split(',')
for(var i = 0;i<arr.length;i++){
    for(var j=0;j<bb.length;j++){
        arr[i].title = bb[i];
    }
}
return arr;
}

调用这个方法之后输出的张三，男，三年二班就已转成unicode编码格式