Question

Can someone point me to a sample solution that I can download? I am having trouble trying to find one.

Answer 1

Create a class library, MyInterfaces, that houses just your interfaces:

Imports System.Runtime.Serialization
Imports System.ServiceModel
' NOTE: You can use the "Rename" command on the context menu to change the interface name "IService" in both code and config file together.
<ServiceContract()>
Public Interface IService

    <OperationContract()>
    Function GetData(ByVal value As Integer) As String

    <OperationContract()>
    Function GetDataUsingDataContract(ByVal composite As CompositeType) As CompositeType

    <OperationContract()>
    Function GetCustomer() As Customer

    ' TODO: Add your service operations here

End Interface

' Use a data contract as illustrated in the sample below to add composite types to service operations.
Public Class Customer

    <DataMember()>
    Public Property Name() As String

    <DataMember()>
    Public Property Age() As Integer

End Class

<DataContract()>
Public Class CompositeType

    <DataMember()>
    Public Property BoolValue() As Boolean
    <DataMember()>
    Public Property StringValue() As String

End Class

Add a Web Service Library project. Set a reference to the above project that contains the above Interfaces. Add the following code to this project:

Imports MyInterfaces

' NOTE: You can use the "Rename" command on the context menu to change the class name "Service" in code, svc and config file together.
Public Class Service
    Implements IService


    Public Function GetData(ByVal value As Integer) As String Implements IService.GetData
        Return String.Format("You entered: {0}", value)
    End Function

    Public Function GetDataUsingDataContract(ByVal composite As CompositeType) As CompositeType Implements IService.GetDataUsingDataContract
        If composite Is Nothing Then
            Throw New ArgumentNullException("composite")
        End If
        If composite.BoolValue Then
            composite.StringValue &= "Suffix"
        End If
        Return composite
    End Function

    Public Function GetCustomer() As MyInterfaces.Customer Implements MyInterfaces.IService.GetCustomer
        Dim x As New Customer
        x.Age = 15
        x.Name = "Chad"
        Return x
    End Function

End Class

Add a 3rd project, a client app which will consume the Service. I’ll make mine a WinForm app. Have this project also reference the Interface projrect. Add this code:

Imports System.ServiceModel
Imports MyInterfaces

Public Class Form1

    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click

        Dim endPoint As New EndpointAddress("http://localhost:9496/WCFService4/Service.svc")
        Dim binding As New BasicHttpBinding()

        Dim proxy As IService = ChannelFactory(Of IService).CreateChannel(binding, endPoint)

        Dim getDateResult As String = proxy.GetData(3)

        Dim myCompositeType As New MyInterfaces.CompositeType
        myCompositeType.BoolValue = True
        myCompositeType.StringValue = "ok"

        Dim result As MyInterfaces.CompositeType = proxy.GetDataUsingDataContract(myCompositeType)
        MessageBox.Show(result.StringValue)
End Sub

This is just a quick and dirty example. My goal was to get rid of the generated proxy object that you normally get when you use the Add Service Wizard. I suppose that end point should come from a config file, though I am not sure how to dynamically determine what the port will be when debugging under VS’ web server.

Dim endPoint As New EndpointAddress("http://localhost:9496/WCFService4/Service.svc")

The one thing that I don’t like about this is that the objects I pass, eg, a Customer object, which represent a potential Business Object, seem to require that they have a default parameterless constructor. I prefer to have constructors to ensure that my object was properly initialized wherever it may have been used.