golang中遍歷匯總

直接上例子：

例子1：

package main

import(
    "fmt"
)

func main(){

    a := map[string]string{
        "alice":"11",
        "bob":"29",
        "zhangsan":"29",
        "wang":"35",
    }

    tmpRs := map[string][]string{}
    for k1, v1 := range a {
        tmpRs[v1] = append(tmpRs[v1], k1)
    }
    
    fmt.Printf("tmpRs.........=%v",tmpRs)
}

根據value，把Value相同的放在一起，結果放在一個大map里.

執行結果如下：

> tmpRs.........=map[11:[alice] 29:[bob zhangsan] 35:[wang]]

 

例子2：

// json.go
package main
 
import (
    "encoding/json"
    "fmt"
    "strconv"
)
  

type FakeUserInfo struct {
    Push_Type              string      `json:"push_type"`       // 渠道
    Third_Token           string      `json:"third_token"`      // token
    User_id                string      `json:"user_id"`         // 用戶ID 
}


//  return: map[int]map[string][]string :{0: {"Users":["2","3","4"],"Tokens":["234","234"]}}
func main() {
    var m FakeUserInfo
    var tmpRs = map[int]map[string][]string{}

    str := `{"push_type": "0","user_id": "fake_22222","third_token": "22222"}`
 
    json.Unmarshal([]byte(str), &m)
    fmt.Println(m)
    fmt.Println("pushType......",m.Push_Type)
    fmt.Println("thirdToken......",m.Third_Token)
    fmt.Println("userId......",m.User_id)

                if len(m.Push_Type) == 0 {
                        return
                }
                i, _ := strconv.Atoi(m.Push_Type)

                if tmpRs[i] == nil {
                    tmpRs[i] = map[string][]string{}
                }
                if tmpRs[i]["Users"] == nil {
                    tmpRs[i]["Users"] = []string{}
                }
                if m.Third_Token == "" || m.User_id == "" {
                     return
                }
                tmpRs[i]["Users"] = append(tmpRs[i]["Users"], m.User_id)
                if tmpRs[i]["Tokens"] == nil {
                    tmpRs[i]["Tokens"] = []string{}
                }
                tmpRs[i]["Tokens"] = append(tmpRs[i]["Tokens"], m.Third_Token)
        
     fmt.Printf("tmpRs.........=%v",tmpRs)
}

 

把結果放在一個復合map中.

執行結果如下：

> {0 22222 fake_22222}
> pushType...... 0
> thirdToken...... 22222
> userId...... fake_22222
> tmpRs.........=map[0:map[Users:[fake_22222] Tokens:[22222]]]