How to add a new item to an object at a specific position with vanilla JS

How to add a new item to an object at a specific position with JS:
  t.ly/uWcQ *** (using function) 
// https://gomakethings.com/how-to-add-a-new-item-to-an-object-at-a-specific-position-with-vanilla-js/

// Main Code Using function:

var addToObject = function (obj, key, value, index) {
	// Create a temp object and index variable
	var temp = {};
	var i = 0;
	// Loop through the original object
	for (var prop in obj) {
		if (obj.hasOwnProperty(prop)) {
			// If the indexes match, add the new item
			if (i === index && key && value) {
				temp[key] = value;
			}
			// Add the current item in the loop to the temp obj
			temp[prop] = obj[prop];
			// Increase the count
			i++;
		}
	}
	// If no index, add to the end
	if (!index && key && value) {
		temp[key] = value;
	}
	return temp;
};

// Output: 

// Original object
var lunch = {
  sandwich: 'turkey',
  drink: 'soda',
  chips: true
};

// Add to the end of the object
var lunchWithDessert = addToObject(lunch, 'dessert', 'cookie');
// Add between sandwich and drink
var lunchWithTopping = addToObject(lunch, 'topping', 'tomato', 1);
// Immutable copy of lunch
var lunchClone = addToObject(lunch);

// In Normal Way: 

let obj = {b: 1, c: 3};
let c = Object.assign({b: null , a: 5, c: null}, obj);
console.log(c);

// let obj = {"1" : "test1","2" : "test2"};
// let c = Object.assign({"key1": "value1"}, obj);
// console.log(c);
// console.log(c['1']); // in that case not happening, new property added to the end


How to add a new item to an object at a specific position with JS:
  t.ly/uWcQ *** (using function) 
// https://gomakethings.com/how-to-add-a-new-item-to-an-object-at-a-specific-position-with-vanilla-js/

// In Normal Way: 

let obj = {b: 1, c: 3};
let c = Object.assign({b: null , a: 5, c: null}, obj);
console.log(c);

// let obj = {"1" : "test1","2" : "test2"};
// let c = Object.assign({"key1": "value1"}, obj);
// console.log(c);
// console.log(c['1']); // in that case not happening, new property added to the end