Corey McClelland

Here is a very simple example of delegates in vb.net.  The DelegateExample class is the entry point in the application. 

The true power of delegates are seen when they are implemented using multiple threads.  That's typically a ui thread and multiple worker threads that update the ui.

Public Class DelegateExample
    Shared Sub main()
        Dim s As New Status()
        s.beginWorker()
    End Sub
End Class

Imports System.Windows.Forms

Public Class Status

    Sub New()

    End Sub

    Public Sub beginWorker()
        Dim w As New Worker()
        w.NotifyOnWorkerEventHapened(New Worker.workerEventHappened(AddressOf localMethod))
        w.beginWork()
    End Sub

    'this function has the same signiture as the delegate
    Public Sub localMethod(ByVal strMsg As String)
        MessageBox.Show(strMsg)
    End Sub

End Class

Public Class Worker

    Public Delegate Sub workerEventHappened(ByVal strMsg As String)
    Private weh As workerEventHappened

    Public Sub NotifyOnWorkerEventHapened(ByVal value As workerEventHappened)
        weh = value
    End Sub

    Sub New()

    End Sub

    Public Sub beginWork()
        weh.Invoke("Event Happened!")
    End Sub

End Class