72 lines
1.5 KiB
Markdown
72 lines
1.5 KiB
Markdown
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---
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id: 587d7dad367417b2b2512b75
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title: Create a Method on an Object
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challengeType: 1
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forumTopicId: 301318
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dashedName: create-a-method-on-an-object
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---
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# --description--
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Objects can have a special type of property, called a <dfn>method</dfn>.
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Methods are properties that are functions. This adds different behavior to an object. Here is the `duck` example with a method:
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```js
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let duck = {
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name: "Aflac",
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numLegs: 2,
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sayName: function() {return "The name of this duck is " + duck.name + ".";}
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};
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duck.sayName();
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// Returns "The name of this duck is Aflac."
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```
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The example adds the `sayName` method, which is a function that returns a sentence giving the name of the `duck`. Notice that the method accessed the `name` property in the return statement using `duck.name`. The next challenge will cover another way to do this.
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# --instructions--
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Using the `dog` object, give it a method called `sayLegs`. The method should return the sentence "This dog has 4 legs."
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# --hints--
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`dog.sayLegs()` should be a function.
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```js
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assert(typeof dog.sayLegs === 'function');
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```
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`dog.sayLegs()` should return the given string - note that punctuation and spacing matter.
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```js
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assert(dog.sayLegs() === 'This dog has 4 legs.');
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```
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# --seed--
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## --seed-contents--
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```js
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let dog = {
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name: "Spot",
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numLegs: 4,
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};
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dog.sayLegs();
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```
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# --solutions--
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```js
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let dog = {
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name: "Spot",
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numLegs: 4,
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sayLegs () {
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return 'This dog has ' + this.numLegs + ' legs.';
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}
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};
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dog.sayLegs();
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```
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