How to Get Class Name in JavaScript

1. Use the instanceof Operator to Get the Class Name in JavaScript
2. Use the name Property to Get the Class Name in JavaScript
3. Use the typeof Operator to Get the Class Name in JavaScript
4. Use the isPrototypeOf() Function to Get the Class Name in JavaScript

In JavaScript, you may need to get the name of a class from time to time. This is useful when utilizing the class name as an identifier or for debug messages.

In JavaScript, there is no equivalent to Java’s getClass() function because Java is a class-based language, whereas JavaScript is a prototype-based language.

In this tutorial, we will get the class name in JavaScript.

Use the instanceof Operator to Get the Class Name in JavaScript

The instanceof operator does not directly give the class name but can check if the constructor’s prototype property occurs anywhere in the object’s prototype chain.

For example,

function Test() {}
let test = new Test();
console.log(test instanceof Test);

Output:

true

In the above example, test belongs to Test, and that is why it returns true.

Use the name Property to Get the Class Name in JavaScript

We can use the name property of the object’s constructor to know the class name in JavaScript. This way, we get the name of that class through which we have instantiated the object.

For Example,

function Test() {}
let test = new Test();
console.log(test.constructor.name);
console.log(Test.name);

Output:

Test
Test

Use the typeof Operator to Get the Class Name in JavaScript

The typeof operator returns a string that indicates the type of the operand.

For Example,

function Test() {}
let test = new Test();
console.log(typeof Test);
console.log(typeof test);

Output:

function
object

Use the isPrototypeOf() Function to Get the Class Name in JavaScript

The function isPrototypeOf() function determines whether an object is another object’s prototype. First, we need to use the prototype property of the object.

See the following example,

function Test() {}
let test = new Test();
console.log(Test.prototype.isPrototypeOf(test));

Output:

true