使用 VB.NET 进行动态 JSON 反序列化 [重复]

Question

我收到以下格式的 JSON 格式的 API 响应

{
    "stuffs": {
        "prop1": "abcd",
        "prop2": "efgh",
        "prop3": [
            {
                "content": "123456",
                "name": "abc def",
                "id": "123"
            },
            {
                "content": "789012",
                "name": "def ghi",
                "id": "456"
            }
        ]
    }
}

我已经创建了我的类来反序列化这个对象，如下所示

Public Class Prop3
    Public Property content As String
    Public Property name As String
    Public Property id As String
End Class

Public Class Stuffs
    Public Property prop1 As String
    Public Property prop2 As String
    Public Property prop3 As Prop3()
End Class

Public Class Example
    Public Property stuffs As Stuffs
End Class

现在的问题是，有时响应不是 prop3 的数组，看起来像这样

{
    "stuffs": {
        "prop1": "abcd",
        "prop2": "efgh",
        "prop3": {
            "content": "123456",
            "name": "abc def",
            "id": "123"
        }
    }
}

这次我在反序列化时出错，因为 prop3 不再是数组，而是在我的类材料中声明的属性需要一个属性 prop3 的数组。

有没有动态的方法来解决这个问题？就像 JSON 响应是一个数组一样，它将被视为数组

Public Property prop3 As Prop3()

如果它不是一个数组，那么它将被视为单个属性

Public Property prop3 As Prop3

请建议如何克服这个问题，因为更改 API 的响应是不可行的，因为它是由客户端开发的，我需要在我的应用程序中使用它，所以我需要找到一些动态的方法来解决这个问题。

根据Craig的建议，我尝试了以下方法，但仍然没有发生，如果我犯了任何错误，请提出建议。

Public Class SingleValueArrayConverter(Of T)
    Inherits JsonConverter

    Public Overrides Sub WriteJson(ByVal writer As JsonWriter, ByVal value As Object, ByVal serializer As JsonSerializer)
        serializer.Serialize(writer, value)
    End Sub

    Public Overrides Function ReadJson(ByVal reader As JsonReader, ByVal objectType As Type, ByVal existingValue As Object, ByVal serializer As JsonSerializer) As Object
        Dim retVal As Object = New Object()

        If reader.TokenType = JsonToken.StartObject Then
            Dim instance As T = CType(serializer.Deserialize(reader, GetType(T)), T)
            retVal = New List(Of T)() From {
                instance
            }
        ElseIf reader.TokenType = JsonToken.StartArray Then
            retVal = serializer.Deserialize(reader, objectType)
        End If

        Return retVal
    End Function

    Public Overrides Function CanConvert(ByVal objectType As Type) As Boolean
        Return True
    End Function
End Class


Public Class myClass1
    Public Class Prop3
        Public Property content As String
        Public Property name As String
        Public Property id As String
    End Class

    Public Class Stuffs
        Public Property prop1 As String
        Public Property prop2 As String
        <JsonProperty("prop3")>
        <JsonConverter(GetType(SingleValueArrayConverter(Of Prop3)))>
        Public Property prop3 As Prop3()
    End Class

    Public Class Example
        Public Property stuffs As Stuffs
    End Class
End Class

它给出错误： 无法将类型为“SingleValueArrayConverter`1[myClass1.myClass+Prop3]”的对象转换为类型“Newtonsoft.Json.JsonConverter”。

请强调一下我所缺少的。

Answer 1

修改后效果很好

Public Property prop3 As Prop3()

到

Public Property prop3 As List(Of Prop3)