--- id: 587d7daf367417b2b2512b7d title: Iterate Over All Properties challengeType: 1 forumTopicId: 301320 --- ## Description <section id='description'> You have now seen two kinds of properties: <code>own</code> properties and <code>prototype</code> properties. <code>Own</code> properties are defined directly on the object instance itself. And <code>prototype</code> properties are defined on the <code>prototype</code>. ```js function Bird(name) { this.name = name; //own property } Bird.prototype.numLegs = 2; // prototype property let duck = new Bird("Donald"); ``` Here is how you add <code>duck</code>'s <code>own</code> properties to the array <code>ownProps</code> and <code>prototype</code> properties to the array <code>prototypeProps</code>: ```js let ownProps = []; let prototypeProps = []; for (let property in duck) { if(duck.hasOwnProperty(property)) { ownProps.push(property); } else { prototypeProps.push(property); } } console.log(ownProps); // prints ["name"] console.log(prototypeProps); // prints ["numLegs"] ``` </section> ## Instructions <section id='instructions'> Add all of the <code>own</code> properties of <code>beagle</code> to the array <code>ownProps</code>. Add all of the <code>prototype</code> properties of <code>Dog</code> to the array <code>prototypeProps</code>. </section> ## Tests <section id='tests'> ```yml tests: - text: The <code>ownProps</code> array should include <code>"name"</code>. testString: assert(ownProps.indexOf('name') !== -1); - text: The <code>prototypeProps</code> array should include <code>"numLegs"</code>. testString: assert(prototypeProps.indexOf('numLegs') !== -1); - text: You should solve this challenge without using the built in method <code>Object.keys()</code>. testString: assert(!/\Object.keys/.test(code)); ``` </section> ## Challenge Seed <section id='challengeSeed'> <div id='js-seed'> ```js function Dog(name) { this.name = name; } Dog.prototype.numLegs = 4; let beagle = new Dog("Snoopy"); let ownProps = []; let prototypeProps = []; // Add your code below this line ``` </div> </section> ## Solution <section id='solution'> ```js function Dog(name) { this.name = name; } Dog.prototype.numLegs = 4; let beagle = new Dog("Snoopy"); let ownProps = []; let prototypeProps = []; for (let prop in beagle) { if (beagle.hasOwnProperty(prop)) { ownProps.push(prop); } else { prototypeProps.push(prop); } } ``` </section>