What is the constructor in JavaScript?

This article mainly introduces what the constructor in JavaScript refers to, which has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, let the editor take you to understand it.

1. Also known as forged objects or borrowed constructors, the supertype constructor is called inside the subtype constructor.

2. A function is just an object that executes code in a specific environment. Therefore, through the apply () and call () methods, the constructor can be executed on the new object.

That is, the initialization code for all objects defined in the parent type function is executed on the subtype object. As a result, each subclass instance has properties and methods in the parent type, which are not inherited, but called.

Example

/ / Classical inheritance (pseudo inheritance) function Animal (name,age) {this.name = name; this.name = age;} function Dog (name,age,color) {Animal.call (this,name,age); / / the parent class constructor animal is called in the subclass to execute the parent class method this.color = color;} var D1 = new Dog ('xb',2,'white'); console.log (D1) / / Dog {name: 2, color: 'white'} Thank you for reading this article carefully. I hope the article "what the constructor in JavaScript refers to" shared by the editor will be helpful to you. At the same time, I also hope you will support us and pay attention to the industry information channel. More related knowledge is waiting for you to learn!