Q
Which of the following will result in an error when using a constant object in JavaScript?

Answer & Solution

Answer: Option C
Solution:
Reassigning the object reference to a new object will result in an error when using a constant object in JavaScript because the reference is constant.
Related Questions on Average

What is the data type of a constant object in JavaScript?

A). A. Object

B). B. Array

C). C. Function

D). D. String

What is the output of the following code snippet?

A). A. { a: 1, b: 2, c: 3 }

B). B. { a: 1, b: 2 }

C). C. { c: 3 }

D). D. Error

What is the result of the expression Object.keys(person).length for the following code snippet?

A). A. 1

B). B. 2

C). C. 3

D). D. Error

What is the output of the following code snippet?

A). A. { x: 10, y: 20 }

B). B. { x: 20, y: 10 }

C). C. { x: 10 }

D). D. Error

What happens if you try to modify a property of a frozen object in JavaScript using Object.freeze()?

A). A. The property is modified successfully

B). B. A TypeError is thrown

C). C. The property is deleted

D). D. The object becomes mutable

What happens if you try to delete a property from a constant object in JavaScript?

A). A. The property is deleted successfully

B). B. A TypeError is thrown

C). C. A SyntaxError is thrown

D). D. Nothing happens

Which of the following is a valid way to define a constant object in JavaScript?

A). A. const obj = { a: 1, b: 2 };

B). B. const obj = new Object({ a: 1, b: 2 });

C). C. Both A and B

D). D. None of the above

How can you ensure that a constant object remains unchanged in JavaScript?

A). A. Use Object.preventExtensions()

B). B. Use Object.freeze() to freeze the object

C). C. Use const for each property

D). D. All of the above

What happens if you use Object.freeze() on a constant object in JavaScript?

A). A. The object reference becomes mutable

B). B. The properties of the object become immutable

C). C. The object becomes frozen and cannot be modified

D). D. A TypeError is thrown

Which statement about constant objects in JavaScript is correct?

A). A. Constant objects can have their properties reassigned

B). B. Constant objects cannot have properties added or removed

C). C. Constant objects are only applicable to primitive values

D). D. Constant objects are mutable