JavaScript Classesconstructor()Methods

JavaScript 类(class)JavaScript Classes

Examples

Examples

Created a class named "Example", and initialized the class:

class Example { constructor(name, url) { this.name = name; this.url = url; } } let site = new Example("Example", "https://www.example.com");

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Definition and Usage

The constructor() method is a special method (constructor) used to create and initialize objects created within a class.

The constructor() method is automatically called when creating an object.

If no constructor method is explicitly specified, a default constructor method is added.

If a constructor method is not specified, a default constructor is used.

Within a constructor, the super keyword can be used to call a parent class's constructor.

Syntax

constructor(parameters)


Technical Details

JavaScript Version: ECMAScript 2015 (ES6)

Browser Support

constructor() is an ECMAScript6 (ES6) feature.

ES6 (JavaScript 2015) is supported by all current major browsers.

Chrome Edge Firefox Safari Opera
Yes Yes Yes Yes Yes

Internet Explorer 11 or older versions of IE do not support the constructor() method.


JavaScript 类(class)JavaScript Classes Other Extensions