1 class User {
 2     constructor(name, age) {
 3         this.name = name;
 4         this.age = age;
 5     }
 6 
 7     changeName(name) {
 8         this.name = name;
 9     }
10 
11     changeAge(age) {
12         this.age = age;
13     }
14 
15     chage(name, age) {
16 
17         //
 
 本this -> 獲取的是全局的this
18         var self = this;
19         let fn = () => {
20 　　　　　　//無論嵌套多少層 -> 只要通過箭頭符號獲取的就是全局的
21             (() => {
22                 (() => {
23                     (() => {
24                         console.log(‘全局this：‘, self);
25                         this
 
.changeAge(age);
26                         this.changeName(name);
27                     })();
28                 })()
29             })()
30 
31             console.log(‘全局this：‘, self);
32             this.changeAge(age);
33             this.changeName(name);
34         }
35 
36         //
 
 function fn() {
37         //     // 當前 - 帶箭頭 -> 全局
38         //     this.changeAge(age);
39         //     this.changeName(name);
40         // }
41 
42         fn();
43     }
44 
45 
46 }
47 
48 var user = new User(‘zhang‘, 30);
49 user.chage(‘long‘, 20);
50 
51 console.log(‘chage修改後：‘, user);
52 
53 
54 
55 //  函數 -es5
56 function calc(x, y) {
57     return x * y;
58 }
59 
60 console.log(calc(1, 5));
61 
62 //  函數 -es6
63 var es6calc = (x, y) => {
64     return x * y;
65 }
66 
67 console.log(es6calc(1, 2));

es6 - 箭頭