附加来自 GO MAP 的关键数据

Question

I have a map in GO of the type :

var userinputmap = make(map[string]string)

The values in it are like :

userinputmap["key1"] = value1
userinputmap["key2"] = value2
userinputmap["key3"] = value3

How can I generate a string that contains al the above keys in comma seprated format?

output:= "key1,key2,key3"

Answer 1

iterate in a loop and append key to string:

package main

import "fmt"

func main() {
    var userinputmap = make(map[string]string)

    userinputmap["key1"] = "value1"
    userinputmap["key2"] = "value2"
    userinputmap["key3"] = "value3"
    output :=""
    for key,_ := range userinputmap {
    output +=(key+",")
    }
    output = output[:len(output)-1]
    fmt.Println(output)
}

Answer 2

Another option is to collect all your keys into a slice and then use strings.Join method to join them.

package main

import "fmt"
import "strings"

func main() {
    var userinputmap = make(map[string]string)

    userinputmap["key1"] = "value1"
    userinputmap["key2"] = "value2"
    userinputmap["key3"] = "value3"

    keys := []string {}

    for k, _ := range userinputmap {
        keys = append(keys, k)
    }

    keys_string := strings.Join(keys, ",")

    fmt.Println(keys_string)
}