Javascript Quiz

 What does the typeof operator return when used with an array in JavaScript?

• array

• object

• array-object

• undefined

Which of the following is true about the localStorage object in JavaScript?

• stores data on the server-side.

• It stores data only for the duration of the session.

• It stores data permanently even after the browser is closed.

• It cannot store data in key-value pairs.

.      Which method is used to add new elements to the end of an array in JavaScript?

• push()

• pop()

• shift()

• unshift()

What is the purpose of the querySelectorAll() method in JavaScript?

• To select the first element that matches a specified CSS selector

• To select all elements that match a specified CSS selector

• To modify the CSS of an element

• To create a new HTML element

What does the filter() method do in JavaScript?

• Removes elements from an array based on a condition and returns a new array

• Adds new elements to an array

• Sorts the elements of an array

• Reverses the order of the elements in an array

Which statement correctly declares a function in JavaScript?

• function = myFunction() {}

• var myFunction = function() {}

• function myFunction() {}

• myFunction() = function() {}

What is the purpose of the Math.random() function in JavaScript?

• It generates a random number between 0 (inclusive) and 1 (exclusive).

• It rounds a number to the nearest integer.

• It calculates the square root of a number.

• It generates a random integer between two specified values.

What does the substring() method do in JavaScript?

• Extracts a section of a string and returns it as a new string.

• Replaces a specified value with another value in a string.

• Converts a string to uppercase.

• Converts a string to lowercase.

What is the purpose of the addEventListener() method in JavaScript?

• It adds an event listener to an HTML element, specifying the function to run when the event occurs.

• It removes an event listener from an HTML element.

• It creates a new HTML element.

• It triggers an event on an HTML element.

What is the purpose of the isNaN() function in JavaScript?

• To check if a value is an integer

• To check if a value is not a number

• To check if a value is a number

• To check if a value is null