freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript/accessing-nested-objects.en...

2.3 KiB

id title challengeType videoUrl
56533eb9ac21ba0edf2244cc Accessing Nested Objects 1 https://scrimba.com/c/cRnRnfa

Description

The sub-properties of objects can be accessed by chaining together the dot or bracket notation. Here is a nested object:
var ourStorage = {
  "desk": {
    "drawer": "stapler"
  },
  "cabinet": {
    "top drawer": {
      "folder1": "a file",
      "folder2": "secrets"
    },
    "bottom drawer": "soda"
  }
};
ourStorage.cabinet["top drawer"].folder2; // "secrets"
ourStorage.desk.drawer; // "stapler"

Instructions

Access the myStorage object and assign the contents of the glove box property to the gloveBoxContents variable. Use bracket notation for properties with a space in their name.

Tests

tests:
  - text: <code>gloveBoxContents</code> should equal "maps"
    testString: assert(gloveBoxContents === "maps", '<code>gloveBoxContents</code> should equal "maps"');
  - text: Use dot and bracket notation to access <code>myStorage</code>
    testString: assert(/=\s*myStorage\.car\.inside\[\s*("|')glove box\1\s*\]/g.test(code), 'Use dot and bracket notation to access <code>myStorage</code>');

Challenge Seed

// Setup
var myStorage = {
  "car": {
    "inside": {
      "glove box": "maps",
      "passenger seat": "crumbs"
     },
    "outside": {
      "trunk": "jack"
    }
  }
};

var gloveBoxContents = undefined; // Change this line

After Test

(function(x) { 
  if(typeof x != 'undefined') { 
    return "gloveBoxContents = " + x;
  }
  return "gloveBoxContents is undefined";
})(gloveBoxContents);

Solution

var myStorage = {
  "car":{
    "inside":{
      "glove box":"maps",
      "passenger seat":"crumbs"
    },
    "outside":{
      "trunk":"jack"
    }
  }
};
var gloveBoxContents = myStorage.car.inside["glove box"];