【发布时间】：2021-01-07 17:07:15
【问题描述】：
我有 json 格式的数据：
{
"status":{
"timestamp":"2021-01-07T17:13:48.471Z",
"error_code":0,
"error_message":null,
"elapsed":12,
"credit_count":1,
"notice":null,
"total_count":4115
},
"data":[
{
"id":1,
"name":"Bitcoin",
"symbol":"BTC",
"slug":"bitcoin",
"num_market_pairs":9732,
"date_added":"2013-04-28T00:00:00.000Z",
"tags":[
"mineable",
"pow",
"sha-256",
"store-of-value",
"state-channels"
],
"max_supply":21000000,
"circulating_supply":18593700,
"total_supply":18593700,
"platform":null,
"cmc_rank":1,
"last_updated":"2021-01-07T17:12:02.000Z",
"quote":{
"USD":{
"price":39362.167971369854,
"volume_24h":78135138852.86674,
"percent_change_1h":2.61231359,
"percent_change_24h":12.47756102,
"percent_change_7d":36.98956944,
"market_cap":731888342609.2596,
"last_updated":"2021-01-07T17:12:02.000Z"
}
}
},
{
"id":1027,
"name":"Ethereum",
"symbol":"ETH",
"slug":"ethereum",
"num_market_pairs":5934,
"date_added":"2015-08-07T00:00:00.000Z",
"tags":[
"mineable",
"pow",
"smart-contracts"
],
"max_supply":null,
"circulating_supply":114155463.749,
"total_supply":114155463.749,
"platform":null,
"cmc_rank":2,
"last_updated":"2021-01-07T17:12:02.000Z",
"quote":{
"USD":{
"price":1261.606649005652,
"volume_24h":39345516218.36576,
"percent_change_1h":3.1558102,
"percent_change_24h":7.80752209,
"percent_change_7d":71.81090319,
"market_cap":144019292086.06207,
"last_updated":"2021-01-07T17:12:02.000Z"
}
}
}
]
}
并且，在 vb.net 中，通过特殊粘贴，我得到了这个定义：
Public Class Rootobject
Public Property status As Status
Public Property data() As Datum
End Class
Public Class Status
Public Property timestamp As Date
Public Property error_code As Integer
Public Property error_message As Object
Public Property elapsed As Integer
Public Property credit_count As Integer
Public Property notice As Object
Public Property total_count As Integer
End Class
Public Class Datum
Public Property id As Integer
Public Property name As String
Public Property symbol As String
Public Property slug As String
Public Property num_market_pairs As Integer
Public Property date_added As Date
Public Property tags() As String
Public Property max_supply As Integer
Public Property circulating_supply As Integer
Public Property total_supply As Integer
Public Property platform As Object
Public Property cmc_rank As Integer
Public Property last_updated As Date
Public Property quote As Quote
End Class
Public Class Quote
Public Property USD As USD
End Class
Public Class USD
Public Property price As Single
Public Property volume_24h As Single
Public Property percent_change_1h As Single
Public Property percent_change_24h As Single
Public Property percent_change_7d As Single
Public Property market_cap As Single
Public Property last_updated As Date
End Class
但是当我尝试使用此命令反序列化时
Dim m As IEnumerable(Of Rootobject) =
JsonConvert.DeserializeObject(Of IEnumerable(Of Rootobject))(res)
我收到此错误：
Newtonsoft.Json.JsonSerializationException: 'Cannot deserialize the current JSON object
(e.g. {"name":"value"}) into type
'System.Collections.Generic.IEnumerable`1[CoinMarketCap.Rootobject]'
because the type requires a JSON array (e.g. [1,2,3])
to deserialize correctly. To fix this error either change the JSON to a
JSON array (e.g. [1,2,3]) or change the deserialized type so that it is a
normal .NET type (e.g. not a primitive type like integer, not a
collection type like an array or List) that can be deserialized from a
JSON object. JsonObjectAttribute can also be added to the type to force
it to deserialize from a JSON object. Path 'status', line 1, position 10.'
我卡住了...有什么想法吗？ 提前致谢。
【问题讨论】：
-
Datum应该是data或者反之亦然，所以它知道它是什么？ -
-
更改为公共属性数据作为列表（基准）并且错误继续...
-
不止一个问题：
tags是Public Property tags As List(Of String)（避免使用这种格式的属性：Public Property tags() As String，因为这会造成 混淆，这是一个字符串，而不是一个数组），circulating_supply，max_supply和total_supply是 Double 而不是 Integer 值，您还必须处理空值，所以用<JsonProperty(NullValueHandling:=NullValueHandling.Ignore)>装饰。所有 Single 应该是 Double，last_updated是 DateTimeOffset，而不是 Date... -
你还在尝试反序列化为
IEnumerable(Of Rootobject)吗？因为那不会发生。如果您更改了代码（修复了类模型定义中的明显错误），请发布更新的代码。假设这是您正在处理的完整 JSON。