go语言接口interface（三）

package main
import "fmt"


/*
一个结构体实现多个接口
*/


type AInterface interface {
	setName(string)
	getName()string
}

type BInterface interface {
	run(string)
}
//接口的嵌套
type Animaler interface  {
	AInterface
	BInterface

}


type Dog struct {
	name string

}
//结构体是值类型，修改需要用指针类型
func(d *Dog) setName(name string){
	d.name=name
}

func(d Dog) getName()string{
	return d.name
}

func(d Dog) run(name string){
	fmt.Printf("%v is running", name)
}


func main() {
	d := &Dog{
		name:"erha",
	}
	var d1 Animaler = d

	fmt.Println(d1.getName())//erha
	d1.setName("二哈")
	fmt.Println(d1.getName())//二哈

	d1.run(d.name)//二哈 is running

}

 

 

package main

import "fmt"

/*
空接口和类型断言的使用注意事项

切片和结构体赋值给空接口，如果访问切片中的某个值，或者访问结构体的某个属性，会报错
*/


type address struct {
	name string
	phone int
}

func main() {

	mp1 := make(map[string]interface{})

	mp1["username"]="lft"
	mp1["age"]=20

	mp1["hobby"] = []string{"python", "golang"}

//	fmt.Println(mp1["hobby"][0])   //type interface {} does not support indexing

	//使用类型断言解决
	hobby,_ := mp1["hobby"].([]string)

	fmt.Println(hobby[0])  //python

	mp1["address"] = address{
		name:"lft",
		phone:[phone],
	}

	fmt.Println(mp1["address"])  //{lft 123456789}

//	fmt.Println(mp1["address"].name)  //type interface {} is interface with no methods
	//断言解决
	address1, _ := mp1["address"].(address)

	fmt.Println(address1.name)  //lft

}