Golang-从结构数组中的值创建字符串

Question

I have a an array of structs that each have an id and a title.

What is the most efficient way of creating a comma separated list of ids from this array.

eg

Struct A - id: 1, title: ....
Struct B - id: 2, title: ....
Struct C - id: 3, title: ....

Need a string "1,2,3"

Answer 1

Iterate the array and append to a buffer.

package main

import (
    "bytes"
    "fmt"
    "strconv"
)

type data struct {
    id   int
    name string
}

var dataCollection = [...]data{data{1, "A"}, data{2, "B"}, data{3, "C"}}

func main() {
    var csv bytes.Buffer
    for index, strux := range dataCollection {
        csv.WriteString(strconv.Itoa(strux.id))
        if index < (len(dataCollection) - 1) {
            csv.WriteString(",")
        }
    }
    fmt.Printf("%s
", csv.String())
}