go解析json的2种方式

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主要有定义struct和interface类型断言2种方式

1. 定义struct

package main

import (
    "encoding/json"
    "fmt"
)

type Student struct {
    Name string `json:"Name"`
    Age  int    `json:"Age"`
    Sex  string `json:"Sex"`
}
type Class struct {
    ClassName string `json:"ClassName"`
    Students  []Student
}
type School struct {
    SchoolName string
    Id         int64 `json:"Id"`
    Class      map[string]Class
}

func main() {

    jsonData := []byte(`
    {
        "SchoolName": "Standard",
        "Class" : {
            "1": {
                "ClassName": "一年级1班",
                "Students": [
                    {
                        "Name":"小明",
                        "Age":5,
                        "Sex":"男"
                    },
                    {
                        "Name":"小花",
                        "Age":5,
                        "Sex":"女"
                    }
                ]
            },
            "2": {
                "ClassName": "一年级2班",
                "Students": [
                    {
                        "Name":"小强",
                        "Age":6,
                        "Sex":"男"
                    },
                    {
                        "Name":"小刚",
                        "Age":5,
                        "Sex":"男"
                    }
                ]
            }
        },
        "Id": 999
    }`)

    var s School
    err := json.Unmarshal(jsonData, &s)
    if err != nil {
        fmt.Println(err)
    }
    for _, class := range s.Class {
        fmt.Println(class.ClassName)
        for _, student := range class.Students {
            fmt.Println(student.Name, student.Age, student.Sex)
        }
    }
}

2. interface类型断言

package main

import (
    "encoding/json"
    "fmt"
)

func main() {

    jsonData := []byte(`
    {
        "SchoolName": "Standard",
        "Class" : {
            "1": {
                "ClassName": "一年级1班",
                "Students": [
                    {
                        "Name":"小明",
                        "Age":5,
                        "Sex":"男"
                    },
                    {
                        "Name":"小花",
                        "Age":5,
                        "Sex":"女"
                    }
                ]
            },
            "2": {
                "ClassName": "一年级2班",
                "Students": [
                    {
                        "Name":"小强",
                        "Age":6,
                        "Sex":"男"
                    },
                    {
                        "Name":"小刚",
                        "Age":5,
                        "Sex":"男"
                    }
                ]
            }
        },
        "Id": 999
    }`)
    var i interface{}
    json.Unmarshal(jsonData, &i)
    data := i.(map[string]interface{})
    for k, v := range data {
        switch v := v.(type) {
            case string:
                fmt.Println("string", k, v)
            case []interface{}:
                for kk, vv := range v {
                        fmt.Println(kk, vv)
                }
            case map[string]interface{}:
                    //fmt.Println("array[string]")
                for kk, vv := range v {
                    switch vv := vv.(type) {
                        case string:
                            fmt.Println("string", kk, vv)
                        case []interface{}:
                                //fmt.Println("array[]", kk)
                        case map[string]interface{}:
                            //fmt.Println("array[string]", kk)
                            for kkk, vvv := range vv {
                                switch vvv := vvv.(type) {
                                    case string:
                                        fmt.Println("string", kkk, vvv)
                                    case []interface{}:
                                        for kkkk, vvvv := range vvv {
                                            switch vvvv := vvvv.(type) {
                                            case string:
                                                fmt.Println(kkkk)
                                            case map[string]interface{}:
                                                for kkkkk, vvvvv := range vvvv {
                                                    fmt.Println(kkkkk, vvvvv)
                                                }
                                            }
                                        }
                                    default:
                                }
                            }
                        default:
                            fmt.Println(" ")
                    }
                }
            default:
                fmt.Println(k, v)
        }
    }

}