JSFiddle - React, Tailwind, and code Playground

JavaScript

function iterateObj(obj, callback){
		if (obj == null || typeof obj != "object"){
			return;
		}
		for (var key in obj){
			// callback(key, obj[key]);
			alert("obj.key--->" + obj.key);
			alert("obj[key]--->" + obj[key]);
			// callback(key, obj.key);
		}

	}

	var sample = {
		start: "bar",
		notes: [{location: "somewhere"}, {time: "someday"}],
		anotherobj: {
			another: "1",
			another1: "3",
			another2: "2"
		},
		end: "foo"
	}
	iterateObj(sample, function(key, value){
		// console.log("key: " + key+ ", " + "value: "+ value);
	})