Answer & Solution
Answer: Option A
Solution:
javascript const obj = { a: 1, b: 2 }; obj.c = 3; console.log(obj); The code adds the c property to the obj object, resulting in { a: 1, b: 2, c: 3 }.
Q
What is the output of the following code snippet?
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
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 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
What does the const keyword do when used to declare an object in JavaScript?
A). A. Makes the object immutable
B). B. Prevents reassignment of the object reference
C). C. Freezes all properties of the object
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
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 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 change the properties of a constant object in JavaScript?
A). A. Use Object.freeze()
B). B. Use const for each property
C). C. Use the delete keyword to remove properties
D). D. Use dot notation or bracket notation
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
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