将切片中的值分组为新类型

Question

我在根据位置将 user1 和 user2 分组到新类型时遇到问题type Chat struct {location stringuserName string}a := Chat{location:Cal, userName:"user1"}b := Chat{location:Cal, userName:"user2"}c := Chat{location:IL, userName:"user3"}type result struct {location stringchat []Chat}

Answer 1

假设您只想按位置字符串分组并从中创建结果结构，则可以使用地图：

type Chat struct {

    location string

    userName string

}

type Result struct {

    location string

    chat     []Chat

}

func main() {

    a := Chat{location: "Cal", userName: "user1"}

    b := Chat{location: "Cal", userName: "user2"}

    c := Chat{location: "IL", userName: "user3"}

    x := []Chat{a, b, c}

    m := make(map[string]Result)

    for _, c := range x {

        if val, ok := m[c.location]; ok {

            chats := append(val.chat, c)

            m[c.location] = Result{location: c.location, chat: chats}

        } else {

            m[c.location] = Result{location: c.location, chat: []Chat{c}}

        }

    }

    for k, v := range m {

        fmt.Printf("%s -> %v\n", k, v)

    }

}

那会回来的

Cal -> {Cal [{Cal user1} {Cal user2}]}

IL -> {IL [{IL user3}]}