package main import ( "database/sql"    "encoding/json"    "fmt"    "github.com/gogf/gf/encoding/gjson"    "github.com/gogf/gf/frame/g"    "github.com/gogf/gf/os/glog"    "reflect" ) func main()  {
  //JsonToStructDemo() } func db_to_json(){
  // 数据库数据转成json字符串输出  db := g.DB("local") r, err:= db.Table("data_all").Where("name=?", "ad1909").One() fmt.Println(sql.ErrNoRows) if err != nil && err == sql.ErrNoRows {
  err = nil  } //字符串数据转json对象  mjson,_ :=json.Marshal(r) mString :=string(mjson) fmt.Println(mString) if k, err := gjson.DecodeToJson([]byte(mString)); err != nil {
  glog.Error(err)    } else {
  fmt.Println(k.Get("name"))    } } // json 转其他格式 func jsonstr_to_other(){
  data := `{
            "users" : {
               "count" : 100,             "list"  : [                {"name" : "小明",  "score" : 60},                {"name" : "John", "score" : 99.5}             ]          }       }`      if j, err := gjson.DecodeToJson([]byte(data)); err != nil {
  glog.Error(err)       } else {
  //==========转json 字符串============================       c, _ := j.ToJson() fmt.Println("JSON:") fmt.Println(string(c)) fmt.Println("======================") fmt.Println("XML:") c, _ = j.ToXmlIndent() fmt.Println(string(c)) fmt.Println("======================") fmt.Println("YAML:") c, _ = j.ToYaml() fmt.Println(string(c)) fmt.Println("======================") fmt.Println("TOML:") c, _ = j.ToToml() fmt.Println(string(c))    } } // 遍历json func json_bianli(){
  data := `{
            "users" : {
               "count" : 100,             "list"  : [                {"name" : "小明",  "score" : 60},                {"name" : "John", "score" : 99.5}             ]          }       }`  if j, err := gjson.DecodeToJson([]byte(data)); err != nil {
  glog.Error(err)       } else {
  //=========================解析成json 两种方法=================       //=============方法1==================================  for _, v := range j.GetArray("users.list") {
  fmt.Println(v.(map[string]interface{})["name"])        //需要强转  } //=============方法2==================================  for _, v := range j.GetJsons("users.list") {
  fmt.Println(v.Get("name"))                    //直接解析  } fmt.Println("John Score:", j.GetFloat32("users.list.1.score")) fmt.Println("John Score:", j.GetInt("users.count"))    } } //=========================================（JSON <--->map） ======================================================= /* map  =======> JSON字符串 */ //例子1 func Map_To_Json_1(){
  m :=map[string]string{
  "type":"10","msg":"hello."} mjson,_ :=json.Marshal(m) mString :=string(mjson) fmt.Printf("print mString:%s",mString) } //例子2 func Map_To_Json_2(){
  mapInstances := []map[string]interface{}{} instance_1 := map[string]interface{}{
  "name": "John", "age": 10} instance_2 := map[string]interface{}{
  "name": "Alex", "age": 12} mapInstances = append(mapInstances, instance_1, instance_2) jsonStr, err := json.Marshal(mapInstances) if err != nil {
  fmt.Println("MapToJsonDemo err: ", err)    } fmt.Println(string(jsonStr)) } /*  JSON字符串 =======>  map */ //例子1 func JsonToMapDemo() {
  jsonStr := `{"name": "jqw","age": 18}`  var mapResult map[string]interface{} err := json.Unmarshal([]byte(jsonStr), &mapResult) if err != nil {
  fmt.Println("JsonToMapDemo err: ", err)    } fmt.Println(mapResult) } //=========================================（JSON <--->map） ======================================================= //=========================================（JSON <--->结构体） ======================================================= type IT struct {
  Address   string   `json:"address"`  Languages []string `json:"languages"` //二次编码  Status    bool     `json:"isok"`  Price     float64  `json:"price"` } /* JSON=======>结构体 */ //例子1 func Json_to_Struct(){
  jsonBuf := `       {
         "address": "北京",       "languages": [          "Golang",          "PHP",          "Java",          "Python"       ],       "status": true,       "price": 666.666    }`  var tmp IT                                   //定义一个结构体变量  err := json.Unmarshal([]byte(jsonBuf), &tmp) //第二个参数要地址传递  if err != nil {
  fmt.Println("err = ", err) return  } fmt.Println("tmp = ", tmp) fmt.Printf("tmp = %+v\n", tmp) /*    tmp =  {北京 [Golang PHP Java Python] false 666.666}    tmp = {Address:北京 Languages:[Golang PHP Java Python] Status:false Price:666.666}    */ } //例子2   使用别名 type People struct {
  Name string `json:"name_title"`  Age int `json:"age_size"` } func JsonToStructDemo(){
  jsonStr := `    {
      "name_title": "jqw",    "age_size":12    }`  var people People  err:=json.Unmarshal([]byte(jsonStr), &people) if err != nil {
  fmt.Println("err = ", err) return  } fmt.Println(people) fmt.Printf("tmp = %+v\n", people) } /*    结构体=======>JSON */ // 例子1 func Struct_To_Json() {
  //定义一个结构体变量，同时初始化  s := IT{
  "itcast", []string{
  "Golang", "PHP", "Java", "C++"}, true, 666.666} //编码，根据内容生成json文本    //buf, err := json.Marshal(s)    //buf =  {"subjects":["Golang","PHP","Java","C++"],"IsOk":"true","Price":"666.666"}  buf, err := json.MarshalIndent(s, "", "    ") //格式化编码  if err != nil {
  fmt.Println("err = ", err) return  } fmt.Println("buf = ", string(buf)) /*    buf =  {
         "address": "itcast",       "languages": [          "Golang",          "PHP",          "Java",          "C++"       ],       "isok": true,       "price": 666.666    }    */ } //=========================================（JSON <--->结构体） ======================================================== //=========================================[]interface{}转json ======================================================= func interface_to_json(){
  var s []interface{} s = append(s,5) s = append(s,[]string{
  "Golang", "PHP", "Java", "Python"}) s = append(s,map[string]string{
  "hello":"world"}) result, err := json.MarshalIndent(s, "", "    ") if err != nil {
  fmt.Println("err = ", err) return  } fmt.Println("result = ", string(result)) } //=========================================[]interface{}转json ======================================================= //=========================================struct=>map======================================================= //需要安装一个第三方库 //在命令行中运行： go get github.com/goinggo/mapstructure func Map2Struct() {
  mapInstances := make(map[string]interface{}) mapInstances["Name"] = "amy"  mapInstances["ID"] = 7  mapInstances["Age"] = 18  var account Account  err := mapstructure.Decode(mapInstances, &account) if err != nil {
  fmt.Println(err)    } fmt.Println(account) } func Struct2Map() {
  account := Account{
  Name: "amy",  ID:   007,  Age:  18,  } obj1 := reflect.TypeOf(account) obj2 := reflect.ValueOf(account) var data = make(map[string]interface{}) for i := 0; i < obj1.NumField(); i++ {
  data[obj1.Field(i).Name] = obj2.Field(i).Interface()    } fmt.Println(data) } //=========================================struct=>map=======================================================