Q
What does the const keyword do when used to declare an object in JavaScript?

Answer & Solution

Answer: Option B
Solution:
The const keyword in JavaScript prevents reassignment of the object reference but does not make the object itself immutable or freeze its properties.
Related Questions on Average

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

A). A. Modifying an existing property

B). B. Adding a new property

C). C. Reassigning the object reference

D). D. None, all operations are valid with constant objects

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

What happens if you try to reassign a constant object to a new object in JavaScript?

A). A. No error, the assignment is successful

B). B. TypeError is thrown

C). C. SyntaxError is thrown

D). D. ReferenceError is thrown

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

How can you prevent modifications to the properties of a JavaScript object?

A). A. Use Object.preventExtensions()

B). B. Use const for each property

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

D). D. All of the above

Which of the following will cause an error when used with a constant object in JavaScript?

A). A. Modifying a property using bracket notation

B). B. Adding a property using dot notation

C). C. Deleting a property

D). D. Reassigning the object reference

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

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

A). A. Object

B). B. Array

C). C. Function

D). D. String

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 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