golang之interface

一、interface

package main

import "fmt"

type USB interface {
    Name() string
    Connect()
}

type PhoneConnecter struct {
    name string
}

func (pc PhoneConnecter) Name() string {
    return pc.name
}

func (pc PhoneConnecter) Connect() {
    fmt.Println(pc.name)
}

func main() {
    var a USB 
    // 将结构体实例赋值给interface
    // interface的value为PhoneConnecter的实例
    a = PhoneConnecter{"PhoneConnecter"}
    a.Connect()
    DisConnect(a)
    DisConnect2(a)
}

func DisConnect(usb USB) {
    fmt.Println("DisConnect")
    if pc, ok := usb.(PhoneConnecter); ok {
        fmt.Println("DisConnect:", pc.name)
        return
    }   
    fmt.Println("unkown device")
}

func DisConnect2(usb interface{}) {
    fmt.Println("DisConnect2")
    switch v := usb.(type) {
    case PhoneConnecter:
        fmt.Println("DisConnect:", v.name)
    default:
        fmt.Println("unkown device")
    }
}