99 lines
2.5 KiB
Markdown
99 lines
2.5 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244c7
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title: Accessing Object Properties with Dot Notation
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cGryJs8'
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---
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## Description
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<section id='description'>
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There are two ways to access the properties of an object: dot notation (<code>.</code>) and bracket notation (<code>[]</code>), similar to an array.
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Dot notation is what you use when you know the name of the property you're trying to access ahead of time.
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Here is a sample of using dot notation (<code>.</code>) to read an object's property:
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```js
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var myObj = {
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prop1: "val1",
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prop2: "val2"
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};
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var prop1val = myObj.prop1; // val1
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var prop2val = myObj.prop2; // val2
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```
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</section>
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## Instructions
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<section id='instructions'>
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Read in the property values of <code>testObj</code> using dot notation. Set the variable <code>hatValue</code> equal to the object's property <code>hat</code> and set the variable <code>shirtValue</code> equal to the object's property <code>shirt</code>.
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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>hatValue</code> should be a string
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testString: assert(typeof hatValue === 'string' , '<code>hatValue</code> should be a string');
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- text: The value of <code>hatValue</code> should be <code>"ballcap"</code>
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testString: assert(hatValue === 'ballcap' , 'The value of <code>hatValue</code> should be <code>"ballcap"</code>');
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- text: <code>shirtValue</code> should be a string
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testString: assert(typeof shirtValue === 'string' , '<code>shirtValue</code> should be a string');
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- text: The value of <code>shirtValue</code> should be <code>"jersey"</code>
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testString: assert(shirtValue === 'jersey' , 'The value of <code>shirtValue</code> should be <code>"jersey"</code>');
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- text: You should use dot notation twice
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testString: assert(code.match(/testObj\.\w+/g).length > 1, 'You should use dot notation twice');
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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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"hat": "ballcap",
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"shirt": "jersey",
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"shoes": "cleats"
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};
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// Only change code below this line
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var hatValue = testObj; // Change this line
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var shirtValue = 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 "hatValue = '" + a + "', shirtValue = '" + b + "'"; })(hatValue,shirtValue);
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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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"hat": "ballcap",
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"shirt": "jersey",
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"shoes": "cleats"
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};
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var hatValue = testObj.hat;
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var shirtValue = testObj.shirt;
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```
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</section>
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