freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../object-oriented-programming/create-a-method-on-an-objec...

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---
id: 587d7dad367417b2b2512b75
title: Create a Method on an Object
challengeType: 1
forumTopicId: 301318
dashedName: create-a-method-on-an-object
---
# --description--
Objects can have a special type of property, called a <dfn>method</dfn>.
Methods are properties that are functions. This adds different behavior to an object. Here is the `duck` example with a method:
```js
let duck = {
name: "Aflac",
numLegs: 2,
sayName: function() {return "The name of this duck is " + duck.name + ".";}
};
duck.sayName();
```
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.
# --instructions--
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-03 00:12:12 +00:00
Using the `dog` object, give it a method called `sayLegs`. The method should return the sentence `This dog has 4 legs.`
# --hints--
`dog.sayLegs()` should be a function.
```js
assert(typeof dog.sayLegs === 'function');
```
`dog.sayLegs()` should return the given string - note that punctuation and spacing matter.
```js
assert(dog.sayLegs() === 'This dog has 4 legs.');
```
# --seed--
## --seed-contents--
```js
let dog = {
name: "Spot",
numLegs: 4,
};
dog.sayLegs();
```
# --solutions--
```js
let dog = {
name: "Spot",
numLegs: 4,
sayLegs () {
return 'This dog has ' + this.numLegs + ' legs.';
}
};
dog.sayLegs();
```