Is constructor method compulsory?

Question

Is constructor method inside the class compulsory even if you don't won't to initialize with starting parameters?

Sam oomen · Accepted Answer

It is not compulsory to define a constructor method for a class in JavaScript. If a class does not have a constructor method, JavaScript will automatically create a default constructor for the class when an object is created from the class. The default constructor simply creates and initializes the object, and does not have any arguments or additional functionality.
Here is an example of a class with a default constructor:
```javascript
class MyClass {
  // No constructor method defined
}
const obj = new MyClass(); // A default constructor is automatically created
```
You can also define your own custom constructor method for a class in JavaScript, which allows you to specify the arguments and functionality of the constructor. Here is an example of a class with a custom constructor method:
```javascript
class MyClass {
  constructor(arg1, arg2) {
    this.arg1 = arg1;
    this.arg2 = arg2;
  }
}
const obj = new MyClass(1, 2); // The custom constructor is called with the arguments 1 and 2
```
So, it is not compulsory to define a constructor method for a class in JavaScript, but you can define a custom constructor if you want to specify the arguments and functionality of the constructor.

rydavim · Answer

Take a look at the MDN constructor page (https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Classes/constructor) for all the ins and outs of this. The short answer is if you don't define a constructor method, your object will use a default one.
If you do not specify a constructor method, a default constructor is used.
Default Constructors:
javascript
// base classes
constructor() {}

javascript
// derived classes
constructor(...args) {
  super(...args);
}

Hopefully that helps, but let me know if you have any questions. Happy coding!

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Rushabha Jain

Rushabha Jain

Is constructor method compulsory?

2 Answers

Sam oomen

Sam oomen

rydavim

rydavim