how to iterate over every property of an object in javascript code example

Example 1: javascript loop through object example

var person={
 	first_name:"johnny",
  	last_name: "johnson",
	phone:"703-3424-1111"
};
for (var property in person) {
  	console.log(property,":",person[property]);
}

Example 2: javascript loop through object properties

for (var prop in obj) {
    if (Object.prototype.hasOwnProperty.call(obj, prop)) {
        // do stuff
    }
}

Example 3: going through every attributes of an object javascript

let a = {x: 200, y: 1}
let attributes = Object.keys(a)
console.log(attributes)
//output: ["x", "y"]