JSON.Net VB deserialize not working

Question

I'm new to VB and trying to write a webservice that exports and imports JSON.

I'm using JSON.NET 3.5 and can serialize fine:

My Token class is:

<DataContract()> _
  Public Class Token
    <DataMember()> _
    Public TokenID As String

    <DataMember()> _
    Public Issued As Date

    <DataMember()> _
    Public Expires As Date

    <DataMember()> _
    Public UserName As String

    <DataMember()> _
    Public CompanyID As String

    <DataMember()> _
    Public ApplicationID As Double

    <DataMember()> _
    Public UserID As Double

    <DataMember()> _
    Public DeviceID As Double

    <DataMember()> _
    Public DeviceSerialNumber As String

    <DataMember()> _
    Public IsValid As Boolean

    <DataMember()> _
    Public DebugText As String

(I started with MS's serialization but thought i'd try JSON.NET)

I serialize with:

Dim ThisToken as New Token ThisToken.DebugText = "blah" and so on

    JSONString = Newtonsoft.Json.JsonConvert.SerializeObject(ThisToken)

And I get this output from the webservice:

{"TokenID":"9eaae348-5cbd-46ac-8ba9-83720ac07740","Issued":"/Date(1300422761886+0800)/","Expires":"/Date(1300465961886+0800)/","UserName":"1234","CompanyID":"6","ApplicationID":1.0,"UserID":29.0,"DeviceID":1.0,"DeviceSerialNumber":"9149520800758","IsValid":true,"DebugText":""}

So far so good I think.

To test that deserialization is working, I thought i'd try and deserialise what I just serialised. So I create a webservice that accepts a string and I paste the above into it.

code to deseralise is:

    Dim ThisToken As New Token

    ThisToken = Newtonsoft.Json.JsonConvert.DeserializeObject(JSonString)

When I run the code using VS2005 internal debug/IE testing, I get an http500 internal server error.

I also get the same problem if I try to deserialize immediately after serializing.

I think part of the problem is that the code I was following was c#; from the json.net page:

Product deserializedProduct = JsonConvert.DeserializeObject<Product>(json);

I can see that in c# there is a <Product> part which is not readily apparant in vb ?

I have no doubt that the newtonsoft json.net product works fine; I'm sure that i'm not doing something right.

Help ?

Andrew

Answer 1

The VB equivalent to

Product deserializedProduct = JsonConvert.DeserializeObject<Product>(json);

is

Dim deserializedProduct as Product = JsonConvert.DeserializeObject(Of Product)(Json)

So I think you want

Dim ThisToken as Token = Newtonsoft.Json.JsonConvert.DeserializeObject(Of Token)(JSonString)