[GO]多态

package main

import "fmt"

type Humaner interface {
    SayHi()
}

type Student struct {
    name string
    id int
}

func (s *Student) SayHi()  {
    fmt.Printf("student %s id %d sayhi 
", s.name, s.id)
}

type Teacher struct {
    group string
    addr string
}

func (t *Teacher) SayHi()  {
    fmt.Printf("Teacher %s addr %s sayhi
", t.group, t.addr)
}

type MyStr string

func (tmp *MyStr) SayHi()  {
    fmt.Printf("%s sayhi
", *tmp)
}

//定义一个普通函数，函数的参数为接口类型
//只有一个函数，可以有不同的表现，这就是多态
func WhoSayHi(i Humaner)  {
    i.SayHi()
}

func main() {
    s := &Student{"baylor", 1}
    t := &Teacher{"Mike", "NJ"}
    var str MyStr = "hello world"
    WhoSayHi(s)
    WhoSayHi(t)
    WhoSayHi(&str)

    //还可以使用其它的方式,创建一个切片
    x := make([]Humaner, 3)
    x[0] = s
    x[1] = t
    x[2] = &str

    //第一个返回下标，第二个返回下标对应的值
    for _, i := range x {
        i.SayHi()
    }
}

执行的结果为

student baylor id 1 sayhi 
Teacher Mike addr NJ sayhi
hello world sayhi
student baylor id 1 sayhi 
Teacher Mike addr NJ sayhi
hello world sayhi