从入门到精通浅析Go语言中如何处理JSON数据

package main

import (
	"encoding/json"
	"fmt"
)

type Person struct {
	Name string `json:"name"`
	Age  int    `json:"age"`
}

func main() {
	p := Person{Name: "Alice", Age: 30}
	
	// 序列化为JSON
	data, err := json.Marshal(p)
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
	
	fmt.Println(string(data))
}

package main

import (
	"encoding/json"
	"fmt"
)

type Person struct {
	Name string `json:"name"`
	Age  int    `json:"age"`
}

func main() {
	jsonData := `{"name":"Bob","age":25}`
	
	var p Person
	err := json.Unmarshal([]byte(jsonData), &p)
	if err != nil {
		fmt.Println("Error:", err)
		return
	}
	
	fmt.Printf("Name: %s, Age: %d\n", p.Name, p.Age)
}

package main

import (
	"encoding/json"
	"fmt"
)

type User struct {
	ID        int      `json:"id"`                           // 指定JSON字段名
	Name      string   `json:"name,omitempty"`               // 空值时忽略
	Email     string   `json:"email,omitempty"`              // 空值时忽略
	Password  string   `json:"-"`                            // 忽略该字段
	Age       int      `json:"age,string"`                   // 序列化为字符串
	Tags      []string `json:"tags,omitempty"`               // 空切片时忽略
	IsActive  bool     `json:"is_active"`                    // 指定JSON字段名
}

func main() {
	u := User{
		ID:       1,
		Name:     "Alice",
		Email:    "",
		Password: "secret",
		Age:      30,
		Tags:     nil,
		IsActive: true,
	}
	
	data, _ := json.Marshal(u)
	fmt.Println(string(data))
}

package main

import (
	"encoding/json"
	"fmt"
	"time"
)

type CustomTime struct {
	time.Time
}

func (ct CustomTime) MarshalJSON() ([]byte, error) {
	return json.Marshal(ct.Format("2006-01-02 15:04:05"))
}

func (ct *CustomTime) UnmarshalJSON(data []byte) error {
	var str string
	if err := json.Unmarshal(data, &str); err != nil {
		return err
	}
	
	t, err := time.Parse("2006-01-02 15:04:05", str)
	if err != nil {
		return err
	}
	
	ct.Time = t
	return nil
}

type Event struct {
	Name      string     `json:"name"`
	Timestamp CustomTime `json:"timestamp"`
}

func main() {
	e := Event{
		Name:      "Meeting",
		Timestamp: CustomTime{time.Now()},
	}
	
	data, _ := json.Marshal(e)
	fmt.Println(string(data))
}

package main

import (
	"encoding/json"
	"fmt"
)

type Address struct {
	Street  string `json:"street"`
	City    string `json:"city"`
	Country string `json:"country"`
}

type Person struct {
	Name    string  `json:"name"`
	Age     int     `json:"age"`
	Address Address `json:"address"`
}

func main() {
	p := Person{
		Name: "Alice",
		Age:  30,
		Address: Address{
			Street:  "123 Main St",
			City:    "Beijing",
			Country: "China",
		},
	}
	
	data, _ := json.MarshalIndent(p, "", "  ")
	fmt.Println(string(data))
}

package main

import (
	"encoding/json"
	"fmt"
)

func main() {
	// 使用map处理动态JSON
	jsonData := `{
		"name": "Alice",
		"age": 30,
		"hobbies": ["reading", "swimming"],
		"address": {
			"city": "Beijing",
			"country": "China"
		}
	}`
	
	var data map[string]interface{}
	json.Unmarshal([]byte(jsonData), &data)
	
	fmt.Println("Name:", data["name"])
	fmt.Println("Age:", data["age"])
	
	// 访问嵌套数据
	if address, ok := data["address"].(map[string]interface{}); ok {
		fmt.Println("City:", address["city"])
	}
}