SortMap：按插入顺序排序后转成json

类似java中的LinkedHashMap，输出的json串是按key的插入顺序排序的

场景

一个java项目，重构为go某一个接口返回的数据结构是和客户端约定好的，有排序规则；返回结果是按key排序的一个map转成的字符串（java中可以直接用LinkedHashMap<String, Object>，然后转json）

源码

  1 package main
  2 
  3 import (
  4     "fmt"
  5     "strings"
  6     "encoding/json"
  7 )
  8 
  9 type Smap []*SortMapNode
 10 
 11 type SortMapNode struct {
 12     Key string
 13     Val interface{}
 14 }
 15 
 16 func (c *Smap) Put(key string, val interface{}) {
 17     index, _, ok := c.get(key)
 18     if ok {
 19         (*c)[index].Val = val
 20     } else {
 21         node := &SortMapNode{Key: key, Val: val}
 22         *c = append(*c, node)
 23     }
 24 }
 25 
 26 func (c *Smap) Get(key string) (interface{}, bool) {
 27     _, val, ok := c.get(key)
 28     return val, ok
 29 }
 30 
 31 func (c *Smap) get(key string) (int, interface{}, bool) {
 32     for index, node := range *c {
 33         if node.Key == key {
 34             return index, node.Val, true
 35         }
 36     }
 37     return -1, nil, false
 38 }
 39 
 40 func ToSortedMapJson(smap *Smap) string {
 41     s := "{"
 42     for _, node := range *smap {
 43         v := node.Val
 44         isSamp := false
 45         str := ""
 46         switch v.(type){
 47             case *Smap:
 48                 isSamp = true
 49                 str = ToSortedMapJson(v.(*Smap))
 50         }
 51         
 52         if(!isSamp){
 53             b, _ := json.Marshal(node.Val)
 54             str = string(b)
 55         }
 56         
 57         s = fmt.Sprintf("%s\"%s\":%s,", s, node.Key, str)
 58     }
 59     s = strings.TrimRight(s, ",")
 60     s = fmt.Sprintf("%s}", s)
 61     return s
 62 }
 63 
 64 type testStruct struct{
 65     name string
 66     value interface{}
 67 }
 68 
 69 func main(){
 70     smap := &Smap{}
 71     
 72     n1 := []int{5, 6}
 73     n2 := []string{"s3", "s4"}
 74     n3 := []string{"s1", "s2"}
 75     n4 := []interface{}{"a",5,6.7}
 76     n4 = append(n4, "t")
 77     n4 = append(n4, 1)
 78     n4 = append(n4, 3.2)
 79     
 80     s1 := &Smap{}
 81     s1.Put("first", "1str")
 82     s1.Put("second", "2str")
 83     s1.Put("third", "3str")
 84     
 85     s2 := &Smap{}
 86     var t2 testStruct
 87     t2.name = "testname"
 88     t2.value = s2
 89     s2.Put("s1", s1)
 90     
 91     arr2 := []string{"str1", "str2"}
 92     s2.Put("arr2", arr2)
 93     
 94     smap.Put("1int", n1)
 95     smap.Put("2string", n2)
 96     smap.Put("3string", n3)
 97     smap.Put("4interface", n4)
 98     smap.Put("5smap", s1)
 99     smap.Put("6interfaceSmap", s2)
100 
101     s := ToSortedMapJson(smap)
102     fmt.Println(s)
103 }

 

运行结果(格式化后的json)

 1 {
 2     "1int": [5, 6],
 3     "2string": ["s3", "s4"],
 4     "3string": ["s1", "s2"],
 5     "4interface": ["a", 5, 6.7, "t", 1, 3.2],
 6     "5smap": {
 7         "first": "1str",
 8         "second": "2str",
 9         "third": "3str"
10     },
11     "6interfaceSmap": {
12         "s1": {
13             "first": "1str",
14             "second": "2str",
15             "third": "3str"
16         },
17         "arr2": ["str1", "str2"]
18     }
19 }

 

posted @ 2018-03-19 16:39  笑笑爸  阅读(3083)  评论(0)  编辑  收藏  举报