interface

Posted 2021-03-21 chenguifeng

 1 package main
 2 
 3 import "fmt"
 4 
 5 type Human struct {
 6     name  string
 7     age   int
 8     phone string
 9 }
10 
11 type Student struct {
12     Human  //匿名字段
13     school string
14     loan   float32
15 }
16 
17 type Employee struct {
18     Human   //匿名字段
19     company string
20     money   float32
21 }
22 
23 //Human实现SayHi方法
24 func (h Human) SayHi() {
25     fmt.Printf("Hi, I am %s you can call me on %s
", h.name, h.phone)
26 }
27 
28 //Human实现Sing方法
29 func (h Human) Sing(lyrics string) {
30     fmt.Println("La la la la...", lyrics)
31 }
32 
33 //Employee重载Human的SayHi方法
34 func (e Employee) SayHi() {
35     fmt.Printf("Hi, I am %s, I work at %s. Call me on %s
", e.name,
36         e.company, e.phone)
37 }
38 
39 // Interface Men被Human,Student和Employee实现
40 // 因为这三个类型都实现了这两个方法
41 type Men interface {
42     SayHi()
43     Sing(lyrics string)
44 }
45 
46 func main() {
47     mike := Student{Human{"Mike", 25, "222-222-XXX"}, "MIT", 0.00}
48     paul := Student{Human{"Paul", 26, "111-222-XXX"}, "Harvard", 100}
49     sam := Employee{Human{"Sam", 36, "444-222-XXX"}, "Golang Inc.", 1000}
50     tom := Employee{Human{"Tom", 37, "222-444-XXX"}, "Things Ltd.", 5000}
51 
52     //定义Men类型的变量i
53     var i Men
54 
55     //i能存储Student
56     i = mike
57     fmt.Println("This is Mike, a Student:")
58     i.SayHi()
59     i.Sing("November rain")
60 
61     //i也能存储Employee
62     i = tom
63     fmt.Println("This is tom, an Employee:")
64     i.SayHi()
65     i.Sing("Born to be wild")
66 
67     //定义了slice Men
68     fmt.Println("Let‘s use a slice of Men and see what happens")
69     x := make([]Men, 3)
70     //这三个都是不同类型的元素，但是他们实现了interface同一个接口
71     x[0], x[1], x[2] = paul, sam, mike
72 
73     for _, value := range x {
74         value.SayHi()
75     }
76 }