有意思，值传递后，指针访问修改原有的值

package main

import "fmt"

type data struct {
num int
key *string
items map[string]bool
}

func (this *data) pointerFunc() {
this.num = 7
}

func (this data) valueFunc() {
this.num = 8
*this.key = "valueFunc.key"
this.items["valueFunc"] = true
}

func main() {
key := "key1"

d := data{1, &key, make(map[string]bool)}
fmt.Printf("num=%v  key=%v  items=%v\n", d.num, *d.key, d.items)

d.pointerFunc() // 修改 num 的值为 7
fmt.Printf("num=%v  key=%v  items=%v\n", d.num, *d.key, d.items)

d.valueFunc()   // 修改 key 和 items 的值
fmt.Printf("num=%v  key=%v  items=%v\n", d.num, *d.key, d.items)

}