"节点的类型必须是'JsonObject'。

Question

我正在尝试解析这个Json

代码：

Dim streamData As Stream = Nothing
Using http As New HttpClient
Dim url As String = "https://api.hotbit.io/api/v1/market.deals?market=KIBA/USDT&limit=150&last_id=1521100930&api_key=44812d8f-66d3-01c0-94c3b29305040b03&sign=98EEC3D69D3F70F9BDFED901984B2AA4"
Dim t As Task(Of Stream) = http.GetStreamAsync(url)
streamData = t.Result
End Using
Dim jsonResponse As JsonNode = JsonNode.Parse(streamData)
Dim result As JsonObject = jsonResponse("result").AsObject
Dim c As String = String.Empty
For Each kvp In result.AsEnumerable
c &= kvp.Value("price").ToString & vbCr
Next
RichTextBox1.Text = c
End Sub

但我在调试时一直收到错误

节点的类型必须为"JsonObject"在线

Dim result As JsonObject = jsonResponse("result").AsObject

它是如何产生错误的？如果我已经在尝试将其解析为Jsonobject？

感谢

Answer 1

试试这个。。

• 将其粘贴到一个新的类文件中：

Namespace HotBit
Partial Public Class TradeCollection
<JsonProperty("error")>
Public Property [Error] As Object
<JsonProperty("result")>
Public Property Result As List(Of Result)
<JsonProperty("id")>
Public Property Id As Long
End Class
Partial Public Class Result
<JsonProperty("id")>
Public Property Id As Long
<JsonProperty("time")>
Public Property Time As Long
<JsonProperty("price")>
Public Property Price As String
<JsonProperty("amount")>
<JsonConverter(GetType(ParseStringConverter))>
Public Property Amount As Long
<JsonProperty("type")>
Public Property Type As TypeEnum
End Class
Public Enum TypeEnum
Buy
Sell
End Enum
Partial Public Class TradeCollection
Public Shared Function FromJson(ByVal json As String) As TradeCollection
Return JsonConvert.DeserializeObject(Of TradeCollection)(json, Settings)
End Function
End Class
Public Module Serialize
<Extension()>
Public Function ToJson(ByVal self As TradeCollection) As String
Return JsonConvert.SerializeObject(self, Settings)
End Function
End Module
Friend Module Converter
Public ReadOnly Settings As JsonSerializerSettings = New JsonSerializerSettings With {
.MetadataPropertyHandling = MetadataPropertyHandling.Ignore,
.DateParseHandling = DateParseHandling.None
}
End Module
Friend Class ParseStringConverter
Inherits JsonConverter
Public Overrides Function CanConvert(ByVal t As Type) As Boolean
Return t Is GetType(Long) OrElse t Is GetType(Long?)
End Function
Public Overrides Function ReadJson(ByVal reader As JsonReader, ByVal t As Type, ByVal existingValue As Object, ByVal serializer As JsonSerializer) As Object
If reader.TokenType = JsonToken.Null Then Return Nothing
Dim value = serializer.Deserialize(Of String)(reader)
Dim l As Long
If Long.TryParse(value, l) Then
Return l
End If
Throw New Exception("Cannot unmarshal type long")
End Function
Public Overrides Sub WriteJson(ByVal writer As JsonWriter, ByVal untypedValue As Object, ByVal serializer As JsonSerializer)
If untypedValue Is Nothing Then
serializer.Serialize(writer, Nothing)
Return
End If
Dim value = CLng(untypedValue)
serializer.Serialize(writer, value.ToString())
Return
End Sub
Public Shared ReadOnly Singleton As ParseStringConverter = New ParseStringConverter()
End Class
Friend Class TypeEnumConverter
Inherits JsonConverter
Public Overrides Function CanConvert(ByVal t As Type) As Boolean
Return t Is GetType(TypeEnum) OrElse t Is GetType(TypeEnum?)
End Function
Public Overrides Function ReadJson(ByVal reader As JsonReader, ByVal t As Type, ByVal existingValue As Object, ByVal serializer As JsonSerializer) As Object
If reader.TokenType = JsonToken.Null Then Return Nothing
Dim value = serializer.Deserialize(Of String)(reader)
Select Case value
Case "buy"
Return TypeEnum.Buy
Case "sell"
Return TypeEnum.Sell
End Select
Throw New Exception("Cannot unmarshal type TypeEnum")
End Function
Public Overrides Sub WriteJson(ByVal writer As JsonWriter, ByVal untypedValue As Object, ByVal serializer As JsonSerializer)
If untypedValue Is Nothing Then
serializer.Serialize(writer, Nothing)
Return
End If
Dim value = CType(untypedValue, TypeEnum)
Select Case value
Case TypeEnum.Buy
serializer.Serialize(writer, "buy")
Return
Case TypeEnum.Sell
serializer.Serialize(writer, "sell")
Return
End Select
Throw New Exception("Cannot marshal type TypeEnum")
End Sub
Public Shared ReadOnly Singleton As TypeEnumConverter = New TypeEnumConverter()
End Class
End Namespace

• 然后安装Newtonsoft(如果还没有(和Importsit

• 然后Imports HotBit(或者，如果您更改了上面"粘贴此"的命名空间，则导入该新命名空间

• 然后执行您的请求并查询结果，例如：

Sub Main(args As String())
Dim s = New WebClient().DownloadString("https://api.hotbit.io/api/v1/market.deals?market=KIBA/USDT&limit=150&last_id=1521100930&api_key=44812d8f-66d3-01c0-94c3b29305040b03&sign=98EEC3D69D3F70F9BDFED901984B2AA4")
Dim tc = TradeCollection.FromJson(s)
Dim prices = String.Join(","c, tc.Result.Select(Function(r) r.Price))
End Sub