Map

定义

m := map[string] string {
  "name": "Nick",
  "age": "12",
  "sex": "male",
}

例子

package main

import "fmt"

func main() {

    //create map
    m := map[string] string {
        "name": "Nick",
        "age": "12",
        "sex": "male",
    }
    fmt.Println(m)

    m2 := make(map[string]int)  //m2 == empty map
    fmt.Println(m2)

    var m3 map[string]int       //m3 = nil
    fmt.Println(m3)

    //  map的遍历
    for k, v := range m{
        fmt.Println(k,v)
    }

    // map获取值
    name := m["name"]
    fmt.Printf("name=%v\n",name)

    name1 := m["name1"]
    fmt.Printf("name1=%v\n",name1)

    name2, ok := m["name2"]
    fmt.Printf("name2=%v,ok=%t\n",name2, ok)

    if name3, ok := m["name3"]; ok {
        fmt.Printf(name3)
    }else {
        fmt.Printf("can't find name3\n")
    }
    //set new value
    m["name"]="new name"
    fmt.Println(m)
}