freeCodeCamp

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id	title	challengeType	videoUrl	forumTopicId
56533eb9ac21ba0edf2244c8	Accessing Object Properties with Bracket Notation	1	https://scrimba.com/c/cBvmEHP	16163

Description

The second way to access the properties of an object is bracket notation ([]). If the property of the object you are trying to access has a space in its name, you will need to use bracket notation. However, you can still use bracket notation on object properties without spaces. Here is a sample of using bracket notation to read an object's property:

var myObj = {
  "Space Name": "Kirk",
  "More Space": "Spock",
  "NoSpace": "USS Enterprise"
};
myObj["Space Name"]; // Kirk
myObj['More Space']; // Spock
myObj["NoSpace"];    // USS Enterprise

Note that property names with spaces in them must be in quotes (single or double).

Instructions

Read the values of the properties "an entree" and "the drink" of testObj using bracket notation and assign them to entreeValue and drinkValue respectively.

Tests

tests:
  - text: <code>entreeValue</code> should be a string
    testString: assert(typeof entreeValue === 'string' );
  - text: The value of <code>entreeValue</code> should be <code>"hamburger"</code>
    testString: assert(entreeValue === 'hamburger' );
  - text: <code>drinkValue</code> should be a string
    testString: assert(typeof drinkValue === 'string' );
  - text: The value of <code>drinkValue</code> should be <code>"water"</code>
    testString: assert(drinkValue === 'water' );
  - text: You should use bracket notation twice
    testString: assert(code.match(/testObj\s*?\[('|")[^'"]+\1\]/g).length > 1);

Challenge Seed

// Setup
var testObj = {
  "an entree": "hamburger",
  "my side": "veggies",
  "the drink": "water"
};

// Only change code below this line

var entreeValue = testObj;   // Change this line
var drinkValue = testObj;    // Change this line

After Test

(function(a,b) { return "entreeValue = '" + a + "', drinkValue = '" + b + "'"; })(entreeValue,drinkValue);

Solution

var testObj = {
  "an entree": "hamburger",
  "my side": "veggies",
  "the drink": "water"
};
var entreeValue = testObj["an entree"];
var drinkValue = testObj['the drink'];

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