JS Object Oriented Basics

First, some descriptions of JS object-oriented

1. The functions of object-oriented languages ​​generally include: encapsulation, inheritance, polymorphism, aggregation (combining multiple objects to achieve more complex functions)

2. Objects generally consist of properties, methods, and constructors.

3. JavaScript does not have the concept of a class. To create an object, you only need to define a constructor for the object and create an object through it.

4. This pointer is also applicable to JS

Second, the declaration of the constructor

function Object_Name(arg1,arg2,...(argument list)){
//declare properties and initialize
this.arg1 = arg1;
this.arg2 = arg2;
     ......
//Methods for defining objects, generally there are getter, setter methods for calling and modifying properties, and other methods
this.method1_name = function(null parameter or parameter list){
        // method body
         }
}

 Third, the instantiation of the object

var object name = new Object_Name(parameter list);

Fourth, the object's properties and method calls

object_name.property_name or object.method_name

5. The prototype property

You can add object properties or methods outside the constructor through the prototype property

For example: (where Object_name is the constructor name, and the object name is the instantiated name)

1. Add new properties

Object_name.prototype. The new property name added (generally its initialization value is null);

2. Add new methods

Object_name.prototype.new method name = function(null parameter or parameter list) {

            // method body

}