Object use cases in Javascript - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create an object with a property 'name' set to 'Alice'.

Javascript

const person = { name: [1] };

Drag options to blanks, or click blank then click option'

A'Alice'

BAlice

C"name"

Dname

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around string values.

Using the property name instead of the value.

The property value must be a string, so it needs quotes around 'Alice'.

2fill in blank

medium

Complete the code to access the 'age' property from the object 'user'.

Javascript

const age = user[1]age;

Drag options to blanks, or click blank then click option'

A['']

B::

C->

D.

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect symbols like '->' or '::'.

Using brackets without quotes.

Use dot notation to access properties in JavaScript objects.

3fill in blank

hard

Fix the error in the code to add a new property 'city' with value 'Paris' to the object 'location'.

Javascript

location[1]city = 'Paris';

Drag options to blanks, or click blank then click option'

A[]

B->

C.

D::

Attempts:

3 left

💡 Hint

Common Mistakes

Using arrow or double colon symbols.

Trying to use brackets without quotes.

Use dot notation to add or update properties in an object.

4fill in blank

hard

Fill both blanks to create an object 'scores' with keys as player names and values as their points, but only include players with points greater than 10.

Javascript

const scores = {};
for (const player of players) {
  if (player.points > 10) {
    scores[[1]] = [2];
  }
};

Drag options to blanks, or click blank then click option'

Aplayer.name

Bplayer.points

Cplayer.score

Dplayer.value

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong property names like score or value.

Mixing keys and values.

Use player.name as key and player.points as value to build the object with correct data.

5fill in blank

hard

Fill all three blanks to create a function that returns an object with keys as uppercase names and values as ages, but only for people older than 18.

Javascript

function adultAges(people) {
  return people.reduce((acc, [1]) => {
    if ([2].age > 18) {
      acc[[3]] = [2].age;
    }
    return acc;
  }, {});
}

Drag options to blanks, or click blank then click option'

Aperson

Bp

Cp.name.toUpperCase()

Dperson.name.toUpperCase()

Attempts:

3 left

💡 Hint

Common Mistakes

Using different variable names inconsistently.

Not converting names to uppercase.

Mixing parameter names in different places.

Use 'p' as the parameter, check p.age, and use p.name.toUpperCase() as key to build the object.