Question

I’m trying to raise an event in a mocked interface. I can get this in C#, but for some pain-in-the-butt reason can’t get it working in VB.Net. If someone could help me out with this situation, I’d appreciate it. Hopefully I haven’t missed the boat conceptually and all I’m missing is some syntax. This is similar to the code I’m working with:

Public Interface ISendable

Event SendMessage(message As String)

End Interface

''**********

Public Interface IPrintable

Sub PrintAnnouncement(announcement As String)

End Interface

'******

Public Class BulletinBoard

Private mPrintable As IPrintable

Public Sub New(sendable As ISendable, printable As IPrintable)
    AddHandler sendable.SendMessage, AddressOf GetItOut
    mPrintable = printable
End Sub

Public Sub GetItOut(message As String)
    'Do some stuff I can verify happened with Moq
    mPrintable.PrintAnnouncement(message)
End Sub
End Class

I was hoping to get a test that looked something like this running:

Imports NUnit.Framework
Imports Moq

<TestFixture()> _
Public Class SendMessageTests

<Test()> _
Public Sub canRaiseEvent()
    Dim announcement As String = "What the?"
    Dim sendable As New Mock(Of ISendable)()
    Dim printable As New Mock(Of IPrintable)()

    Dim bb As New BulletinBoard(sendable.Object, printable.Object)
    'What is the syntax for raising sendable's event?
    'sendable.Raise( ....? )

    printable.Verify(Sub(d) d.PrintAnnouncement(announcement), Times.Once())

End Sub

End Class

Can anyone help me to complete or correct the line in my test class that begins “sendable.Raise…”? Maybe there is more setup I need to do, but the Moq site didn’t seem to indicate this is the case.

Thanks in advance.

Answer 1

With this line your test is green:

sendable.Raise(Sub(e) AddHandler e.SendMessage, AddressOf MockHandler, announcement)

You also need to create a “mock” event handler to make it work:

Sub MockHandler()

End Sub

EDIT:

I’m not a VB guy, so it seams there is a shorter syntax with using an inline anonymous method instead of MockHandler:
:

sendable.Raise(Sub(e) AddHandler e.SendMessage, Function() vbEmpty, announcement)