Question

What is the difference between the 'instanceOf' and 'typeOf' operators in JavaScript?

A. 'InstanceOf' checks the data type of a value, while 'typeOf' checks if an object is an instance of a particular constructor or class.
B. 'InstanceOf' is used to check if a variable is declared, while 'typeOf' is used to check the type of an object.
C. 'InstanceOf' is used for comparing two objects for equality, while 'typeOf' is used for type conversion.
D. 'InstanceOf' checks if an object is an instance of a particular constructor or class, while 'typeOf' checks the data type of a value.

Answer 1

The D. 'instanceOf' operator checks if an object is an instance of a particular class or constructor, while the 'typeOf' operator returns a string indicating the type of the operand, such as 'number' or 'object'.

Step-by-step explanation:

The difference between the 'instanceOf' and 'typeOf' operators in JavaScript is that 'instanceOf' checks if an object is an instance of a particular constructor or class, while 'typeOf' returns a string indicating the type of the unevaluated operand. To clarify, 'typeOf' can tell you whether a value is a number, string, boolean, undefined, symbol, or object. However, it is limited when it comes to distinguishing different types of objects, such as between an array and a plain object, as both will return 'object'.

On the other hand, 'instanceOf' can determine if an object is derived from a specific class or constructed by a particular function. For example, if you have a 'Dog' class, you can check whether a 'myPet' variable is an instance of 'Dog' using myPet instanceof Dog, which will return a boolean.