golang json遍历

遍历 JSON 可以使用 Go 语言内置的 encoding/json 包。

假设有以下 JSON 数据：

{
  "name": "John",
  "age": 30,
  "email": "john@example.com",
  "address": {
    "street": "123 Main St",
    "city": "New York",
    "state": "NY",
    "zip": "10001"
  },
  "phoneNumbers": [
    {
      "type": "home",
      "number": "555-1234"
    },
    {
      "type": "work",
      "number": "555-5678"
    }
  ]
}

可以使用以下代码遍历该 JSON：

package main

import (
    "encoding/json"
    "fmt"
)

func main() {
    jsonData := `{
        "name": "John",
        "age": 30,
        "email": "john@example.com",
        "address": {
            "street": "123 Main St",
            "city": "New York",
            "state": "NY",
            "zip": "10001"
        },
        "phoneNumbers": [
            {
                "type": "home",
                "number": "555-1234"
            },
            {
                "type": "work",
                "number": "555-5678"
            }
        ]
    }`

    var result map[string]interface{}
    err := json.Unmarshal([]byte(jsonData), &result)
    if err != nil {
        fmt.Println("error:", err)
    }

    for key, value := range result {
        switch valueType := value.(type) {
        case string:
            fmt.Println(key, "is string:", valueType)
        case float64:
            fmt.Println(key, "is float64:", valueType)
        case map[string]interface{}:
            fmt.Println(key, "is an object:")
            for subKey, subValue := range valueType {
                fmt.Println(subKey, ":", subValue)
            }
        case []interface{}:
            fmt.Println(key, "is an array:")
            for i, arrValue := range valueType {
                fmt.Println(i, ":", arrValue)
            }
        default:
            fmt.Println(key, "is of a different type")
        }
    }
}

输出结果为：

name is string: John
age is float64: 30
email is string: john@example.com
address is an object:
street : 123 Main St
city : New York
state : NY
zip : 10001
phoneNumbers is an array:
0 : map[number:555-1234 type:home]
1 : map[number:555-5678 type:work]

可以看到，遍历 JSON 数据需要使用类型断言，判断当前值的类型，并根据类型进行相应操作。