今日不肯埋头，明日何以抬头！每日一句努力自己的话哈哈~哈喽，今天我将给大家带来一篇《json unmarshal 是否有“any”标签？》，主要内容是讲解等等，感兴趣的朋友可以收藏或者有更好的建议在评论提出，我都会认真看的！大家一起进步，一起学习！
问题内容我想对 coinmarketcap 进行两次调用，两次调用的响应几乎相同，只有一个 id 不同
如果我使用 id="1" 进行调用，那么响应结构将是这样的
{
"status": {
"timestamp": "2022-01-31t11:08:10.552z",
"error_code": 0,
"error_message": null,
"elapsed": 29,
"credit_count": 1,
"notice": null
},
"data": {
"1": {
"id": 1,
"name": "bitcoin",
"symbol": "btc",
"slug": "bitcoin",
"num_market_pairs": 9121,
"date_added": "2013-04-28t00:00:00.000z",
"max_supply": 21000000,
[...]
"last_updated": "2022-01-31t11:06:00.000z",
"quote": {
"usd": {
"price": 37287.959833145724,
"volume_24h": 16426509863.271738,
"volume_change_24h": -5.6098,
"percent_change_1h": 0.18350099,
"percent_change_24h": -2.27056162,
"percent_change_7d": 11.98926671,
"percent_change_30d": -20.53627257,
"percent_change_60d": -33.95545743,
"percent_change_90d": -40.97732382,
"market_cap": 706414097373.7339,
"market_cap_dominance": 41.8173,
"fully_diluted_market_cap": 783047156496.06,
"last_updated": "2022-01-31t11:06:00.000z"
}
}
}
}
}当我使用 id="1027" 进行相同的 api 调用时，响应会更改其结构
{
"status": {
"timestamp": "2022-01-31t11:46:02.894z",
"error_code": 0,
"error_message": null,
"elapsed": 28,
"credit_count": 1,
"notice": null
},
"data": {
"1027": {
"id": 1027,
"name": "ethereum",
"symbol": "eth",
"slug": "ethereum",
"num_market_pairs": 5482,
"date_added": "2015-08-07t00:00:00.000z",
"max_supply": null,
[...]
"last_updated": "2022-01-31t11:44:00.000z",
"quote": {
"usd": {
"price": 2535.692637309123,
"volume_24h": 10427616453.128471,
"volume_change_24h": -6.6085,
"percent_change_1h": -0.23965775,
"percent_change_24h": -3.07033246,
"percent_change_7d": 12.35705047,
"percent_change_30d": -31.64459631,
"percent_change_60d": -44.12893821,
"percent_change_90d": -42.93608624,
"market_cap": 302724966788.3792,
"market_cap_dominance": 17.9889,
"fully_diluted_market_cap": 302724966788.38,
"last_updated": "2022-01-31t11:44:00.000z"
}
}
}
}
}在声明结构时是否有可能使用 json:"*any" ？
现在，如果我用 1 (json:"1") 声明它，它只适用于 btc
type CoinInfoResponse struct {
Status struct {
Timestamp time.Time `json:"timestamp"`
ErrorCode int `json:"error_code"`
ErrorMessage interface{} `json:"error_message"`
Elapsed int `json:"elapsed"`
CreditCount int `json:"credit_count"`
Notice interface{} `json:"notice"`
} `json:"status"`
Data struct {
Coin struct {
ID int `json:"id"`
Name string `json:"name"`
Symbol string `json:"symbol"`
Slug string `json:"slug"`
NumMarketPairs int `json:"num_market_pairs"`
DateAdded time.Time `json:"date_added"`
Tags []struct {
Slug string `json:"slug"`
Name string `json:"name"`
Category string `json:"category"`
} `json:"tags"`
MaxSupply interface{} `json:"max_supply"`
CirculatingSupply float64 `json:"circulating_supply"`
TotalSupply float64 `json:"total_supply"`
Platform struct {
ID int `json:"id"`
Name string `json:"name"`
Symbol string `json:"symbol"`
Slug string `json:"slug"`
TokenAddress string `json:"token_address"`
} `json:"platform"`
IsActive int `json:"is_active"`
CmcRank int `json:"cmc_rank"`
IsFiat int `json:"is_fiat"`
LastUpdated time.Time `json:"last_updated"`
Quote struct {
USD struct {
Price float64 `json:"price"`
Volume24H float64 `json:"volume_24h"`
PercentChange1H float64 `json:"percent_change_1h"`
PercentChange24H float64 `json:"percent_change_24h"`
PercentChange7D float64 `json:"percent_change_7d"`
PercentChange30D float64 `json:"percent_change_30d"`
PercentChange60D float64 `json:"percent_change_60d"`
PercentChange90D float64 `json:"percent_change_90d"`
MarketCap float64 `json:"market_cap"`
LastUpdated time.Time `json:"last_updated"`
} `json:"USD"`
} `json:"quote"`
} `json:"1"`
} `json:"data"`
}正确答案
您需要一个自定义解组器。它应该首先解析“id”，然后解组内部 {...} 对象。
示例（https://go.dev/play/p/co12qwKBFpc）：
package main
import (
"bytes"
"encoding/json"
"fmt"
"log"
"strings"
)
const input = `
{
"status": {
"error_code": 100
},
"data": {
"12345": {
"id": 12345,
"name": "aaaaa",
"symbol": "bbbb"
}
}
}`
type data struct {
TagName string
Coin struct {
ID int `json:"id"`
Name string `json:"name"`
Symbol string `json:"symbol"`
// other fileds skipped
}
}
func (d *data) UnmarshalJSON(b []byte) error {
idx := bytes.Index(b, []byte(":"))
// cut "number" and put into TagName
d.TagName = strings.Trim(string(b[:idx-1]), "{\":\n ")
// unmarshal internal {} object
return json.Unmarshal(b[idx+1:len(b)-1], &d.Coin)
}
type Response struct {
Status struct {
ErrorCode int `json:"error_code"`
} `json:"status"`
Data data
}
func main() {
var resp Response
if err := json.Unmarshal([]byte(input), &resp); err != nil {
log.Fatal(err)
}
fmt.Printf("%+v\n", resp)
}本篇关于《json unmarshal 是否有“any”标签？》的介绍就到此结束啦，但是学无止境，想要了解学习更多关于Golang的相关知识，请关注编程网公众号！
