100 lines
2.0 KiB
Markdown
100 lines
2.0 KiB
Markdown
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---
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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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forumTopicId: 16164
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dashedName: accessing-object-properties-with-dot-notation
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---
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# --description--
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There are two ways to access the properties of an object: dot notation (`.`) and bracket notation (`[]`), 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 (`.`) 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;
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var prop2val = myObj.prop2;
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```
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`prop1val` would have a value of the string `val1`, and `prop2val` would have a value of the string `val2`.
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# --instructions--
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Read in the property values of `testObj` using dot notation. Set the variable `hatValue` equal to the object's property `hat` and set the variable `shirtValue` equal to the object's property `shirt`.
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# --hints--
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`hatValue` should be a string
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```js
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assert(typeof hatValue === 'string');
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```
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The value of `hatValue` should be the string `ballcap`
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```js
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assert(hatValue === 'ballcap');
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```
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`shirtValue` should be a string
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```js
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assert(typeof shirtValue === 'string');
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```
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The value of `shirtValue` should be the string `jersey`
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```js
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assert(shirtValue === 'jersey');
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```
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You should use dot notation twice
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```js
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assert(code.match(/testObj\.\w+/g).length > 1);
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```
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# --seed--
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## --after-user-code--
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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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## --seed-contents--
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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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# --solutions--
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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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