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 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
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
What is the correct way to modify a property of a constant object in JavaScript?
A). A. Use the delete keyword
B). B. Use the const keyword for the property
C). C. Use dot notation or bracket notation to access and modify the property
D). D. Use Object.freeze() to freeze the object
Which statement is true about constant objects in JavaScript?
A). A. The properties of a constant object cannot be changed
B). B. Constant objects are frozen and immutable
C). C. Constant objects cannot have properties added or deleted
D). D. The object reference can be reassigned
Which statement best describes the behavior of a constant object in JavaScript?
A). A. The object and its properties cannot be changed
B). B. The object reference cannot be reassigned
C). C. All properties are immutable
D). D. The object cannot be modified after declaration
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 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 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 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