golang ----map按key排序

实现map遍历有序

1. key有序

思路：对key排序，再遍历key输出value

代码如下：既可以从小到大排序，也可以从大到小排序

package main

import (
	"fmt"
	"sort"
)

func main() {
	// To create a map as input
	m := make(map[int]string)
	m[1] = "a"
	m[2] = "c"
	m[0] = "b"

	// To store the keys in slice in sorted order
	var keys []int
	for k := range m {
		keys = append(keys, k)
	}
	sort.Ints(keys)

	// To perform the opertion you want
	for _, k := range keys {
		fmt.Println("Key:", k, "Value:", m[k])
	}
}

　　输出结果：

Key: 0 Value: b
Key: 1 Value: a
Key: 2 Value: c

　　实例2

package main

import (

    "fmt"

    "sort"

)

func main() {

    // To create a map as input

    m := make(map[string]int)

    m["tom"] = 2

    m["jame"] = 4

    m["amy"] = 5

    // To store the keys in slice in sorted order

    var strs []string

    for k := range m {

        strs = append(strs, k)

    }

    sort.Strings(strs)

    // To perform the opertion you want

    for _, k := range strs {

        fmt.Printf("%s\t%d\n", k, m[k])

    }

}

　　

输出结果：

amy 5

jame 4

tom 2