sorting - 如何按其值对 Map[string]int 进行排序？

Question

鉴于此代码块

map[string]int {"hello":10, "foo":20, "bar":20}

我想打印出来

foo, 20
bar, 20
hello, 10

按照从高到低的顺序

Answer 1

在 Andrew Gerrand 的 Golang-nuts 上找到答案

您可以通过编写 len/less/swap 函数来实现排序接口(interface)

func rankByWordCount(wordFrequencies map[string]int) PairList{
  pl := make(PairList, len(wordFrequencies))
  i := 0
  for k, v := range wordFrequencies {
    pl[i] = Pair{k, v}
    i++
  }
  sort.Sort(sort.Reverse(pl))
  return pl
}

type Pair struct {
  Key string
  Value int
}

type PairList []Pair

func (p PairList) Len() int { return len(p) }
func (p PairList) Less(i, j int) bool { return p[i].Value < p[j].Value }
func (p PairList) Swap(i, j int){ p[i], p[j] = p[j], p[i] }

原帖请看这里https://groups.google.com/forum/#!topic/golang-nuts/FT7cjmcL7gw