golang之interface

 1 package main
 2 
 3 import "fmt"
 4 
 5 type USB interface {
 6     Name() string
 7     Connect()
 8 }
 9 
10 type PhoneConnecter struct {
11     name string
12 }
13 
14 func (pc PhoneConnecter) Name() string {
15     return pc.name
16 }
17 
18 func (pc PhoneConnecter) Connect() {
19     fmt.Println(pc.name)
20 }
21 
22 func main() {
23     var a USB 
24     // 将结构体实例赋值给interface
25     // interface的value为PhoneConnecter的实例
26     a = PhoneConnecter{"PhoneConnecter"}
27     a.Connect()
28     DisConnect(a)
29     DisConnect2(a)
30 }
31 
32 func DisConnect(usb USB) {
33     fmt.Println("DisConnect")
34     if pc, ok := usb.(PhoneConnecter); ok {
35         fmt.Println("DisConnect:", pc.name)
36         return
37     }   
38     fmt.Println("unkown device")
39 }
40 
41 func DisConnect2(usb interface{}) {
42     fmt.Println("DisConnect2")
43     switch v := usb.(type) {
44     case PhoneConnecter:
45         fmt.Println("DisConnect:", v.name)
46     default:
47         fmt.Println("unkown device")
48     }
49 }