javascript adds object method

In Javascript, objects are a very common data type. These objects can have a variety of different properties and methods, making them very flexible and useful. Sometimes we need to add a new method to an object so that we can better operate it. In this article, we will introduce how to add object methods in Javascript.

First, let’s take a look at the basic structure of a Javascript object:

var myObj = {
  prop1: "value1",
  prop2: "value2",
  myMethod: function() {
    console.log("This is my method.");
  }
}

In this example, we create an object named myObj, which has two Properties: prop1 and prop2. In addition, we also define a method named myMethod. This method is very simple, it just prints out a text. Now let's see how to add new methods to this object.

Two ways to add a new method to an object

Method 1: Directly assign a new method

We can directly add a new method to the object, like this :

myObj.myNewMethod = function() {
  console.log("This is my new method.");
}

In this example, we define a new method named myNewMethod and assign it to myObj. This method is similar to the myMethod defined before, it just prints out a text.

Now, we can call this new method, for example:

myObj.myNewMethod(); // 输出："This is my new method."

This method is very simple, we can write it with any logic and calculations we want.

Method 2: Use the object constructor to add new methods

Another way to add new methods in Javascript is to use the object constructor. This method is slightly more complicated than assigning a new value directly. For example:

function MyObject(prop1, prop2) {
  this.prop1 = prop1;
  this.prop2 = prop2;
  
  this.myMethod = function() {
    console.log("This is my method.");
  }
  
  this.myNewMethod = function() {
    console.log("This is my new method.");
  }
}

var myObj = new MyObject("value1", "value2");

In this example, we define an object constructor named MyObject. This constructor defines two properties, prop1 and prop2, and two methods, myMethod and myNewMethod. Note that the naming rule for constructors starts with a capital letter to distinguish them from other functions.

We also created a new object, myObj. We use the new keyword and the MyObject constructor to create this object, and add the two "value1" and "value2" Strings are passed to the prop1 and prop2 parameters in the constructor.

Now, we can call the two methods myMethod() and myNewMethod():

myObj.myMethod(); // 输出："This is my method."
myObj.myNewMethod(); // 输出："This is my new method."

This method is better than direct assignment The new method is slightly more complex, but it is more conducive to us managing the properties and methods of the object.

Conclusion

Adding object methods in Javascript can be easily achieved. We can add these methods using direct assignment of new methods or using object constructors. Regardless of which method is used, adding new methods makes the object more useful and flexible. During the development process, we often need to add new methods to objects in order to better operate and manage them. This is a very powerful and flexible feature of Javascript, and we need to make good use of it.

The above is the detailed content of javascript adds object method. For more information, please follow other related articles on the PHP Chinese website!