golang map sort

    import (

    "fmt"

    "sort"

)

type MapSorter []Item

type Item struct {

    Key string

    Val int64

}

func NewMapSorter(m map[string]int64) MapSorter {

    ms := make(MapSorter, 0, len(m))

    for k, v := range m {

        ms = append(ms, Item{k, v})

    }

    return ms

}

func (ms MapSorter) Len() int {

    return len(ms)

}

func (ms MapSorter) Less(i, j int) bool {

    return ms[i].Val < ms[j].Val // 按值排序

    //return ms[i].Key < ms[j].Key // 按鍵排序

}

func (ms MapSorter) Swap(i, j int) {

    ms[i], ms[j] = ms[j], ms[i]

}

func main(){

    m  := map[string]int64 {

        "e": 10,

        "a": 2,

        "d": 15,

        "c": 8,

        "f": 1,

        "b": 12,

    }

    ms := NewMapSorter(m)

    sort.Sort(ms)

    for _, item := range ms {

        fmt.Printf("%s:%d\n", item.Key, item.Val)

    }

}