Imports System
Imports System.IO
Imports System.Collections
Imports System.Collections.Generic
Imports System.Runtime.Serialization
Imports ServiceStack
Imports ServiceStack.DataAnnotations
Imports Test.ServiceModel
Imports Test.ServiceModel.Types
Namespace Global
    Namespace Test.ServiceModel
        Public Partial Class HelloWithInheritance
            Inherits HelloBase
            Public Overridable Property Name As String
        End Class
        Public Partial Class HelloWithInheritanceResponse
            Inherits HelloResponseBase
            Public Overridable Property Result As String
        End Class
    End Namespace
    Namespace Test.ServiceModel.Types
        Public Partial Class HelloBase
            Public Overridable Property Id As Integer
        End Class
        Public Partial Class HelloResponseBase
            Public Overridable Property RefId As Integer
        End Class
    End Namespace
End Namespace
VB.NET HelloWithInheritance DTOs
To override the Content-type in your clients, use the HTTP Accept Header, append the .xml suffix or ?format=xml
The following are sample HTTP requests and responses. The placeholders shown need to be replaced with actual values.
POST /xml/reply/HelloWithInheritance HTTP/1.1 
Host: test.servicestack.net 
Accept: application/xml
Content-Type: application/xml
Content-Length: length
<HelloWithInheritance xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Test.ServiceModel">
  <Id xmlns="http://schemas.datacontract.org/2004/07/Test.ServiceModel.Types">0</Id>
  <Name>String</Name>
</HelloWithInheritance>
HTTP/1.1 200 OK Content-Type: application/xml Content-Length: length <HelloWithInheritanceResponse xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Test.ServiceModel"> <RefId xmlns="http://schemas.datacontract.org/2004/07/Test.ServiceModel.Types">0</RefId> <Result>String</Result> </HelloWithInheritanceResponse>