bd68b70f3d
* fix: remove isHidden flag from frontmatter * fix: add isUpcomingChange Co-authored-by: Ahmad Abdolsaheb <ahmad.abdolsaheb@gmail.com> * feat: hide blocks not challenges Co-authored-by: Ahmad Abdolsaheb <ahmad.abdolsaheb@gmail.com> Co-authored-by: Ahmad Abdolsaheb <ahmad.abdolsaheb@gmail.com>
102 lines
2.5 KiB
Markdown
102 lines
2.5 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244c8
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title: Accessing Object Properties with Bracket Notation
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cBvmEHP'
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forumTopicId: 16163
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---
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## Description
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<section id='description'>
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The second way to access the properties of an object is bracket notation (<code>[]</code>). If the property of the object you are trying to access has a space in its name, you will need to use bracket notation.
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However, you can still use bracket notation on object properties without spaces.
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Here is a sample of using bracket notation to read an object's property:
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```js
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var myObj = {
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"Space Name": "Kirk",
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"More Space": "Spock",
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"NoSpace": "USS Enterprise"
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};
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myObj["Space Name"]; // Kirk
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myObj['More Space']; // Spock
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myObj["NoSpace"]; // USS Enterprise
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```
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Note that property names with spaces in them must be in quotes (single or double).
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</section>
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## Instructions
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<section id='instructions'>
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Read the values of the properties <code>"an entree"</code> and <code>"the drink"</code> of <code>testObj</code> using bracket notation and assign them to <code>entreeValue</code> and <code>drinkValue</code> respectively.
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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>entreeValue</code> should be a string
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testString: assert(typeof entreeValue === 'string' );
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- text: The value of <code>entreeValue</code> should be <code>"hamburger"</code>
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testString: assert(entreeValue === 'hamburger' );
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- text: <code>drinkValue</code> should be a string
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testString: assert(typeof drinkValue === 'string' );
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- text: The value of <code>drinkValue</code> should be <code>"water"</code>
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testString: assert(drinkValue === 'water' );
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- text: You should use bracket notation twice
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testString: assert(code.match(/testObj\s*?\[('|")[^'"]+\1\]/g).length > 1);
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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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// Setup
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var testObj = {
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"an entree": "hamburger",
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"my side": "veggies",
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"the drink": "water"
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};
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// Only change code below this line
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var entreeValue = testObj; // Change this line
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var drinkValue = testObj; // Change this line
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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(a,b) { return "entreeValue = '" + a + "', drinkValue = '" + b + "'"; })(entreeValue,drinkValue);
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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 testObj = {
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"an entree": "hamburger",
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"my side": "veggies",
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"the drink": "water"
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};
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var entreeValue = testObj["an entree"];
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var drinkValue = testObj['the drink'];
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```
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</section>
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