OOP in JS: Constructors

You can create an object from the class passing arguments that are then stored inside the object.

We do so using a constructor, a special method of the class.

Here’s an example:

class Person {
  constructor(name) {
    this.name = name
  }
}

When the object is initialized, the constructor method is called, with any parameters passed.

const flavio = new Person('Flavio')

Now we can add methods that use the name property:

class Person {
  constructor(name) {
    this.name = name
  }

  hello() {
    return 'Hello, I am ' + this.name + '.'
  }
}

Notice we used this to reference the class. This is another place where you are going to use this special JavaScript keyword, other than in object methods.

Lessons in this unit:

0: Introduction
1: Classes
2: Class methods
3: Private class properties
4: ▶︎ Constructors
5: Inheritance
6: Prototypes
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