JavaScript Advanced
Basic
This test evaluates your advanced knowledge of JavaScript, including closures, prototypes, async/await patterns, and ES6+ features. To solidify these concepts, explore free resources like JavaScript.info, dive deeper with MDN JavaScript Guide, and follow advanced tutorials on The Net Ninja’s YouTube series.
1
What is the output of 'typeof NaN'?
2
What does the 'bind()' method do?
3
What is the purpose of 'use strict'?
4
Which method converts JSON to JS object?
5
Which keyword declares a block-scoped variable?
6
What does 'this' refer to in a regular function?
7
What is a closure?
8
Which method stops event bubbling?
9
Which data type is immutable?
10
What is a Promise?
11
What is the result of '[] + []'?
12
Which operator checks both type and value?
13
How do you define a class in ES6?
14
What is the default return type of Array.map()?
15
What is the purpose of Symbol in JS?
16
What does 'await' do?
17
What’s the output of typeof null?
18
Which is not a looping structure?
19
What is IIFE?
20
What is the role of setTimeout with 0ms?
21
How to clone an object deeply?
22
What will [...new Set([1
23
What is event delegation?
24
Which lifecycle method runs after render in class components?
25
Which feature allows sharing methods in multiple objects?