Soap Extension and returning Nothing

[khoy]

Hello.

I am writing a web service and I need to use a Soap Extension to add a
custom header that is expected at the destination. I can use the Soap
Extension successfully for adding the header in the AfterSerialize
section and the destination accepts my request and sends back the
appropriate data, but my problem comes when I try to return the data.
Depending on what I do I either get an exception that "the root element
is missing" or being returned Nothing.

The following is where the exception is being generated:

Dim results() As Object = Me.Invoke("ProcessMessage", New Object()
{payload})
payload = CType(results(0), Payload)

I have found some references that ChainStream in the soap extension may
be causing this issue but I am unable to find any mention of exactly
what I have to do or exactly what is causing the issue.

Any and all help is appreciated!

Thanks,

Kelly

[khoy]

Maybe if I give some more information.

I can use the Soap Extension successfully for adding the header in the
AfterSerialize section and the destination accepts my request and sends
back the appropriate data, but my problem comes when I try to return
the data. Depending on what I do in the BeforeDeserialize staage I
either get an exception that "the root element is missing" or being
returned Nothing. I know I am getting proper response back because I
can see the response using Fiddler.

The sub which calls the webservice in my proxy class is:

Public Sub ProcessMessage(ByRef payload As Payload)
Try
Dim results() As Object = Me.Invoke("ProcessMessage", New
Object() {payload})
payload = CType(results(0), Payload)
Catch ex As Exception
Dim em As String = ex.Message()
End Try
End Sub

Some of the code in my soap extension:
Public Overrides Function ChainStream(ByVal stream As Stream) As Stream
MessageStream = stream
InternalStream = New MemoryStream
Return InternalStream
End Function

Sub Copy(ByVal fromStream As Stream, ByVal toStream As Stream)
Dim reader As New StreamReader(fromStream)
Dim writer As New StreamWriter(toStream)
writer.WriteLine(reader.ReadToEnd())
writer.Flush()
End Sub

If I have the following code in the soap extension:

Public Overrides Sub ProcessMessage(ByVal message As
System.Web.Services.Protocols.SoapMessage)
Select Case message.Stage
Case SoapMessageStage.BeforeDeserialize
Copy(MessageStream, InternalStream)
InternalStream.Position = 0

I get Nothing returned.

If I have the following code:

Public Overrides Sub ProcessMessage(ByVal message As
System.Web.Services.Protocols.SoapMessage)
Select Case message.Stage
Case SoapMessageStage.BeforeDeserialize
' do nothing

I get an error which says "the root element is missing."

I really have no idea what my problem is and why i cannot get a value
back. If anyone can offer some advice and/or code to help solve this
problem I would greatly appreciate it!

Thank you,

Kelly