ES5 Object.assign equivalent

Question

I wanted to do something which is very straight-forward using Object.assign.

var firstObj = {name : "Saba H.", rollNo : 1};
var secondObj = {college : "WCE"};
var wholeObj = Object.assign(firstObj, secondObj);

console.log(wholeObj); // {name : "Saba H.", rollNo : 1, college : "WCE"}

As Object.assign is part of ECMAScript6 harmony proposal and not supported across many browsers, is it possible to do with ES5? If not then is there any micro library?

Answer 1

In underscore.js you can use like,

_.extend(firstObj, secondObj);

In jQuery, you can use,

$.extend({},firstObj,secondObj);

In pure javascipt, you can merge n number of objects by using this function:

function mergeObjects() {
    var resObj = {};
    for(var i=0; i < arguments.length; i += 1) {
         var obj = arguments[i],
             keys = Object.keys(obj);
         for(var j=0; j < keys.length; j += 1) {
             resObj[keys[j]] = obj[keys[j]];
         }
    }
    return resObj;
}