CHAPTER 15 TYPE REFLECTION, LATE BINDING, AND ATTRIBUTE-BASED PROGRAMMING
Note By default, a Visual Basic project will not display the References folder within the Solution Explorer. To
add references in a VB project, use the Project Add Reference… menu option of Visual Studio.
The code is (again) intentionally simple.
Imports System.Windows.Forms
Imports CommonSnappableTypes
Public Class VbSnapIn
Implements IAppFunctionality
Public Sub DoIt() Implements CommonSnappableTypes.IAppFunctionality.DoIt
MessageBox.Show("You have just used the VB snap in!")
End Sub
End Class
Notice that applying attributes in the syntax of Visual Basic requires angle brackets (< >) rather than
square brackets ([ ]). Also notice that the Implements keyword is used to implement interface types on a
given class or structure.
Building an Extendable Windows Forms Application
The final step is to create a new C# Windows Forms application (MyExtendableApp) that allows the user
to select a snap-in using a standard Windows Open dialog box. If you have not created a Windows Forms
application before, begin this final project of the chapter by selecting a Windows Forms Application
project from the New Project dialog box of Visual Studio (see Figure 15-7).
Figure 15-7. Creating a new Windows Forms project with Visual Studio
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