相关疑难解决方法(0)

在Go语言规范中,它提到了标签的简要概述:

字段声明后面可以跟一个可选的字符串文字标记,该标记成为相应字段声明中所有字段的属性.标签通过反射界面可见,但否则将被忽略.

// A struct corresponding to the TimeStamp protocol buffer.
// The tag strings define the protocol buffer field numbers.
struct {
  microsec  uint64 "field 1"
  serverIP6 uint64 "field 2"
  process   string "field 3"
}

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这是一个非常简短的解释IMO,我想知道是否有人可以提供我这些标签的用途？

是否可以用未知字段解组 JSON？该字段名称始终不同，但结构是相同的。JSON 是 POST 请求的结果。

我的代码：

package main

import "fmt"
import "encoding/json"

var body = []byte(`{
    "unknown_field": {
            "known_field_1": [[1,2,3,4,5],[10,20,30,40,50],[100,200,300,400,500]],
            "known_field_2": [[11,21,31,41,51]],
            "known_field_3": [[12,22,32,42,52],[14,44,34,44,54]]
        }
}`)

type MyStruct struct {
    MainData map[string]mData `json:"-"`
}

type mData struct {
    knownField1 [][5]int `json:"known_field_1"`
    knownField2 [][5]int `json:"known_field_2"`
    knownField3 [][5]int `json:"known_field_3"`
}

func NewMyStruct() MyStruct {
    ms := MyStruct{}
    ms.MainData = make(map[string]mData)
    return ms
}

func main() {
    myStruct := NewMyStruct()
    if err := json.Unmarshal(body, &myStruct); err != nil {
        panic(err)
    }

    fmt.Println(myStruct) // …

我有这个JSON数据:

{
"InfoA" : [256,256,20000],
"InfoB" : [256,512,15000],
"InfoC" : [208,512,20000],
"DEFAULT" : [256,256,20000]
}

使用JSON-to-Go,我得到了这个Go类型定义:

type AutoGenerated struct {
    InfoA   []int `json:"InfoA"`
    InfoB   []int `json:"InfoB"`
    InfoC   []int `json:"InfoC"`
    DEFAULT []int `json:"DEFAULT"`
}

使用此代码(play.golang.org)

package main

import (
    "encoding/json"
    "fmt"
    "os"
    "strings"
)

func main() {
    type paramsInfo struct {
        InfoA   []int `json:"InfoA"`
        InfoB   []int `json:"InfoB"`
        InfoC   []int `json:"InfoC"`
        DEFAULT []int `json:"DEFAULT"`
    }
    rawJSON := []byte(`{
"InfoA" : [256,256,20000],
"InfoB" : [256,512,15000],
"InfoC" : [208,512,20000],
"DEFAULT" …

我试图使用Golang将API的响应映射到结构.

我在浏览器中查看链接时返回的JSON如下:

{
"GBP": 657.54
}

我只想将它映射到一个简单的结构,如下所示:

type Price struct {
    Name  string
    Value float64
}

这是我目前的代码.

func FetchCoinPrice(fsym string, tsyms string) Price {
    url := fmt.Sprintf("https://min-api.cryptocompare.com/data/price?fsym=" + fsym + "&tsyms=" + tsyms)

    fmt.Println("Requesting data from " + url)

    price := Price{}

    // getting the data using http
    request, err := http.Get(url)
    if err != nil {
        log.Fatal(err.Error())
    }

    // Read the response body using ioutil
    body, err := ioutil.ReadAll(request.Body)
    if err != nil {
        log.Fatal(err.Error())
    }

    defer request.Body.Close()

    if …

有一个关于输入数据的示例。

{\n    "status": "OK",\n    "status_code": 100,\n    "sms": {\n        "79607891234": {\n            "status": "ERROR",\n            "status_code": 203,\n            "status_text": "\xd0\x9d\xd0\xb5\xd1\x82 \xd1\x82\xd0\xb5\xd0\xba\xd1\x81\xd1\x82\xd0\xb0 \xd1\x81\xd0\xbe\xd0\xbe\xd0\xb1\xd1\x89\xd0\xb5\xd0\xbd\xd0\xb8\xd1\x8f"\n        },\n        "79035671233": {\n            "status": "ERROR",\n            "status_code": 203,\n            "status_text": "\xd0\x9d\xd0\xb5\xd1\x82 \xd1\x82\xd0\xb5\xd0\xba\xd1\x81\xd1\x82\xd0\xb0 \xd1\x81\xd0\xbe\xd0\xbe\xd0\xb1\xd1\x89\xd0\xb5\xd0\xbd\xd0\xb8\xd1\x8f"\n        },\n        "79105432212": {\n            "status": "ERROR",\n            "status_code": 203,\n            "status_text": "\xd0\x9d\xd0\xb5\xd1\x82 \xd1\x82\xd0\xb5\xd0\xba\xd1\x81\xd1\x82\xd0\xb0 \xd1\x81\xd0\xbe\xd0\xbe\xd0\xb1\xd1\x89\xd0\xb5\xd0\xbd\xd0\xb8\xd1\x8f"\n        }\n    },\n    "balance": 2676.18\n}\n

{\n    "status": "OK",\n    "status_code": 100,\n    "sms": {\n        "79607891234": {\n            "status": "ERROR",\n            "status_code": 203,\n            "status_text": "\xd0\x9d\xd0\xb5\xd1\x82 \xd1\x82\xd0\xb5\xd0\xba\xd1\x81\xd1\x82\xd0\xb0 \xd1\x81\xd0\xbe\xd0\xbe\xd0\xb1\xd1\x89\xd0\xb5\xd0\xbd\xd0\xb8\xd1\x8f"\n        },\n        "79035671233": {\n            "status": "ERROR",\n            "status_code": 203,\n            "status_text": "\xd0\x9d\xd0\xb5\xd1\x82 \xd1\x82\xd0\xb5\xd0\xba\xd1\x81\xd1\x82\xd0\xb0 \xd1\x81\xd0\xbe\xd0\xbe\xd0\xb1\xd1\x89\xd0\xb5\xd0\xbd\xd0\xb8\xd1\x8f"\n        },\n        "79105432212": {\n            "status": "ERROR",\n            "status_code": …