在VB.Net WebMethod中反序列化JSON无法正常工作

Question

I'm trying to deserialize a JSON object when I call a WebMethod. The deserialization successfully creates the array of object, but the values are "Nothing". What am I doing wrong?

My Object class:

public class Data
{
    public Attribute[] Attributes{ get; set; }
}

public class Attribute
{
    public string Category { get; set; }
    public string Value { get; set; }

}

Here is my WebMethod:

<System.Web.Services.WebMethod()>
Public Shared Function A_Method(ByVal Attributes As Data)
    'do things
End Function

And here is my JSON object that is being passed to the WebMethod:

{"Attributes":[
   {
      "Attribute":{
         "Category":"Category1",
         "Value":"Value1"
      }
   },
   {
      "Attribute":{
         "Category":"Category2",
         "Value":"Value2"
      }
   },
   {
      "Attribute":{
         "Category":"Category3",
         "Value":"Value3"
      }
   },
   {
      "Attribute":{
         "Category":"Category4",
         "Value":"Value4"
      }
   },
   {
      "Attribute":{
         "Category":"Category5",
         "Value":"Value5"
      }
   },
   {
      "Attribute":{
         "Category":"Category6",
         "Value":"Value6"
      }
   },
   {
      "Attribute":{
         "Category":"Category7",
         "Value":"Value7"
      }
   }
]
}

My problem is that I get the array of 7 Attributes with the Category and Value labels, but the values are "Nothing". What am I doing wrong?

Answer 1

Your object model does not match the shown JSON which actually maps to the following

public class Data {        
    public AttributeElement[] Attributes { get; set; }
}

public class AttributeElement {        
    public Attribute Attribute { get; set; }
}

public class Attribute {        
    public string Category { get; set; }        
    public string Value { get; set; }
}

Note how the elements in the array have an Attribute property.

<System.Web.Services.WebMethod()>
Public Shared Function A_Method(ByVal data As Data)
    'do things
    Dim someAttribute = data.Attributes(0).Attribute
    Dim category = someAttribute.Category
    Dim value = someAttribute.Value
    '...
End Function