Go语言基础go接口用法示例详解

type [接口名] interface {
 方法名1(参数列表) 返回值列表
 方法名2(参数列表) 返回值列表
 ...
}

type Isay interface{
  sayHi()
}

//定义接口的实现类
type Chinese struct{}
//实现接口
func (_ *Chinese) sayHi() {
  fmt.Println("中国人说嗨")
}

//中国人
type Chinese struct{}
//美国人
type Americans struct{}
func (this *Chinese) sayHi()  {
  fmt.Println("中国人说嗨")
}
func (this Americans) sayHi()  {
  fmt.Println("美国人说hi")
}
//调用
&Chinese{}.sayHi()
Americans{}.sayHi()

interface{}

var v1 interface{} = 1
var v2 interface{} = "abc"
var v3 interface{} = struct{ X int }{1}

func Fprint(w io.Writer, a ...interface{}) (n int, err error)
func Fprintf(w io.Writer, format string, a ...interface{})
func Fprintln(w io.Writer, a ...interface{})
func Print(a ...interface{}) (n int, err error)
func Printf(format string, a ...interface{})
func Println(a ...interface{}) (n int, err error)

//说话
type Isay interface{
  sayHi()
}
//工作
type Iwork interface{
  work()
}
//定义一个接口，组合了上述两个接口
type IPersion interface{
  Isay
  Iwork
}
type Chinese struct{}
func (_ Chinese) sayHi() {
  fmt.Println("中国人说中国话")
}
func (_ Chinese) work() {
	fmt.Println("中国人在田里工作")
}
//上述接口等价于：
type IPersion2 interface {
	sayHi()
	work()
}

package main
import "fmt"
//中国话
type Isay interface {
	sayHi()
}
//工作
type Iwork interface {
	work()
}
//中国人
type Chinese struct{}
//美国人
type Americans struct{}
func (this *Chinese) sayHi() {
	fmt.Println("中国人说嗨")
}
func (this Americans) sayHi() {
	fmt.Println("美国人说hi")
}
type IPersion interface {
	Isay
	Iwork
}
func (_ Chinese) work() {
	fmt.Println("中国人在田里工作")
}
func main() {
	var chinese Isay = &Chinese{}
	chinese.sayHi()
	Americans{}.sayHi()
	//接口组合
	var ipersion IPersion = &Chinese{}
	ipersion.sayHi()
	ipersion.work()
}