e9212c61d2
* fix: rm assert msg basic-javascript * fix: removed more assert msg args * fix: fixed verbiage Co-Authored-By: Parth Parth <34807532+thecodingaviator@users.noreply.github.com>
115 lines
3.4 KiB
Markdown
115 lines
3.4 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392d0
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title: Build JavaScript Objects
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cWGkbtd'
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---
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## Description
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<section id='description'>
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You may have heard the term <code>object</code> before.
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Objects are similar to <code>arrays</code>, except that instead of using indexes to access and modify their data, you access the data in objects through what are called <code>properties</code>.
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Objects are useful for storing data in a structured way, and can represent real world objects, like a cat.
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Here's a sample cat object:
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```js
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var cat = {
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"name": "Whiskers",
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"legs": 4,
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"tails": 1,
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"enemies": ["Water", "Dogs"]
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};
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```
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In this example, all the properties are stored as strings, such as - <code>"name"</code>, <code>"legs"</code>, and <code>"tails"</code>. However, you can also use numbers as properties. You can even omit the quotes for single-word string properties, as follows:
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```js
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var anotherObject = {
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make: "Ford",
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5: "five",
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"model": "focus"
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};
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```
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However, if your object has any non-string properties, JavaScript will automatically typecast them as strings.
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</section>
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## Instructions
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<section id='instructions'>
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Make an object that represents a dog called <code>myDog</code> which contains the properties <code>"name"</code> (a string), <code>"legs"</code>, <code>"tails"</code> and <code>"friends"</code>.
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You can set these object properties to whatever values you want, as long <code>"name"</code> is a string, <code>"legs"</code> and <code>"tails"</code> are numbers, and <code>"friends"</code> is an array.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>myDog</code> should contain the property <code>name</code> and it should be a <code>string</code>.
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testString: assert((function(z){if(z.hasOwnProperty("name") && z.name !== undefined && typeof z.name === "string"){return true;}else{return false;}})(myDog));
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- text: <code>myDog</code> should contain the property <code>legs</code> and it should be a <code>number</code>.
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testString: assert((function(z){if(z.hasOwnProperty("legs") && z.legs !== undefined && typeof z.legs === "number"){return true;}else{return false;}})(myDog));
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- text: <code>myDog</code> should contain the property <code>tails</code> and it should be a <code>number</code>.
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testString: assert((function(z){if(z.hasOwnProperty("tails") && z.tails !== undefined && typeof z.tails === "number"){return true;}else{return false;}})(myDog));
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- text: <code>myDog</code> should contain the property <code>friends</code> and it should be an <code>array</code>.
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testString: assert((function(z){if(z.hasOwnProperty("friends") && z.friends !== undefined && Array.isArray(z.friends)){return true;}else{return false;}})(myDog));
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- text: <code>myDog</code> should only contain all the given properties.
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testString: assert((function(z){return Object.keys(z).length === 4;})(myDog));
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// Example
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var ourDog = {
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"name": "Camper",
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"legs": 4,
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"tails": 1,
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"friends": ["everything!"]
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};
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// Only change code below this line.
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var myDog = {
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};
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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(function(z){return z;})(myDog);
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var myDog = {
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"name": "Camper",
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"legs": 4,
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"tails": 1,
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"friends": ["everything!"]
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};
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```
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</section>
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