时间:2023-01-12 12:39:13 | 栏目:Golang | 点击:次
buf, err := json.MarshalIndent(s, "", " ") //格式化编码
package main import ( "encoding/json" "fmt" ) //成员变量名首字母必须大写 type IT struct { Company string `json:"-"` //此字段不会输出到屏幕 Subjects []string `json:"subjects"` //二次编码 IsOk bool `json:",string"` Price float64 `json:",string"` } func main() { //定义一个结构体变量,同时初始化 s := IT{"itcast", []string{"Go", "C++", "Python", "Test"}, true, 666.666} //编码,根据内容生成json文本 //{"Company":"itcast","Subjects":["Go","C++","Python","Test"],"IsOk":true,"Price":666.666} //buf, err := json.Marshal(s) buf, err := json.MarshalIndent(s, "", " ") //格式化编码 if err != nil { fmt.Println("err = ", err) return } fmt.Println(string(buf)) }
package main import ( "encoding/json" "fmt" ) func main() { //创建一个map m := make(map[string]interface{}, 4) m["company"] = "itcast" m["subjects"] = []string{"Go", "C++", "Python", "Test"} m["isok"] = true m["price"] = 666.666 //编码成json //result, err := json.Marshal(m) result, err := json.MarshalIndent(m, "", " ") if err != nil { fmt.Println("err = ", err) return } fmt.Println("result = ", string(result)) }
err := json.Unmarshal([]byte(jsonBuf), &tmp) //第二个参数要地址传递
package main import ( "encoding/json" "fmt" ) type IT struct { Company string `json:"company"` Subjects []string `json:"subjects"` //二次编码 IsOk bool `json:"isok"` Price float64 `json:"price"` } func main() { jsonBuf := ` { "company": "itcast", "subjects": [ "Go", "C++", "Python", "Test" ], "isok": 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) type IT2 struct { Subjects []string `json:"subjects"` //二次编码 } var tmp2 IT2 err = json.Unmarshal([]byte(jsonBuf), &tmp2) //第二个参数要地址传递 if err != nil { fmt.Println("err = ", err) return } fmt.Printf("tmp2 = %+v\n", tmp2) }
package main import ( "encoding/json" "fmt" ) func main() { jsonBuf := ` { "company": "itcast", "subjects": [ "Go", "C++", "Python", "Test" ], "isok": true, "price": 666.666 }` //创建一个map m := make(map[string]interface{}, 4) err := json.Unmarshal([]byte(jsonBuf), &m) //第二个参数要地址传递 if err != nil { fmt.Println("err = ", err) return } fmt.Printf("m = %+v\n", m) // var str string // str = string(m["company"]) //err, 无法转换 // fmt.Println("str = ", str) var str string //类型断言, 值,它是value类型 for key, value := range m { //fmt.Printf("%v ============> %v\n", key, value) switch data := value.(type) { case string: str = data fmt.Printf("map[%s]的值类型为string, value = %s\n", key, str) case bool: fmt.Printf("map[%s]的值类型为bool, value = %v\n", key, data) case float64: fmt.Printf("map[%s]的值类型为float64, value = %f\n", key, data) case []string: fmt.Printf("map[%s]的值类型为[]string, value = %v\n", key, data) case []interface{}: fmt.Printf("map[%s]的值类型为[]interface, value = %v\n", key, data) } } }