How to use static methods, attributes and instance attributes of classes in ES6 javascript-JS Tutorial-php.cn

What I bring to you this time is thestaticmethods of classes in ES6javascript, how to use attributes and instance attributes, this article will give you a good analysis.

The class is equivalent to the prototype of the instance. All methods defined in the class will be inheritedby the instance. If you add thestatic keywordbefore a method, it means that the method will not be inherited by the instance. Instead, it is called directly through the class, which is called a "static method".

class Foo { static classMethod() { return 'hello'; } } Foo.classMethod() // 'hello' var foo = new Foo(); foo.classMethod() // TypeError: foo.classMethod is not a function

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In the above code, there is the static keyword before the classMethod method of class Foo, indicating that the method is a static method and can be called directly on class Foo ( Foo.classMethod()), instead of calling it on an instance of class Foo. If a static method is called on an instance, an error is thrown indicating that the method does not exist.

Static methods of parent classes can be inherited by subclasses.

class Foo { static classMethod() { return 'hello'; } } class Bar extends Foo {} Bar.classMethod(); // 'hello'

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In the above code, the parent class Foo has a static method, and the subclass Bar can call this method.
Static methods can also be called from the super object.

class Foo { static classMethod() { return 'hello'; } } class Bar extends Foo { static classMethod() { return super.classMethod() + ', too'; } } Bar.classMethod();

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I believe you have mastered the method after reading the above introduction. For more exciting information, please pay attention to other related articles on the php Chinese website!