当前位置：网站首页>Constructor in JS (emphasis)

Constructor in JS (emphasis)

2022-06-21 21:34:00 【Liujiayi_】

Constructor execution flow :

1. Create a new object immediately
2. Set the new object to the function this, You can use this To reference a new object

3. Execute the code in the function line by line
4. Return the new object as the return value
 

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <script>
      function Person() {
        this.name = " Liujiayi ";
        this.age = 19;
      }
      var P = new Person();
      alert(P.name);
    </script>
  </body>
</html>

  Use instanceof You can check whether an object is an instance of a class * grammar : object instanceof Constructors

If it is , Then return to true, Otherwise return to false
console.log(per instanceof Person);

 console.log( dog instanceof Person);

* All the objects are Object The offspring of ,
* So any object and Object Left instanceof When you check, you will return true

原网站

版权声明
本文为[Liujiayi_]所创，转载请带上原文链接，感谢
https://yzsam.com/2022/172/202206211943491929.html

边栏推荐

猜你喜欢

随机推荐