Professional IronPython

CREATINg THE SImPLE VISUAL BASIC.NET ExTENSIoN
The best place to begin learning how to create extensions is to create a very simple one. The sections 
that follow explore a simple Visual Basic.NET extension. This project creates a simple math library. 
In the process, it demonstrates some unique principles of creating extensions using Visual Basic.NET.
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Creating the Simple Visual Basic.NET Extension
 
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Creating the Project
A Visual Basic.NET extension project is nothing more than the typical class library. The following 
steps help you create the project for this example. You can use the same steps when working with 
the other examples — simply change the project name.
1.
Choose File
➤➤➪➤➤
New
➤➤➪➤➤
Project. You’ll see the New Project dialog box shown in Figure 17-1.
FIgURE 17-1: 
Create a new project to hold your Visual Basic.NET extension.
2.
Choose the Visual Basic folder in the Installed Templates list.
3.
Select .NET Framework 3.5 or an earlier version of the .NET Framework if you’re using 
Visual Studio 2010. Don’t select the .NET Framework 4.0 entry because IronPython won’t 
load extensions based on the .NET Framework 4.0. The list of templates changes when you 
change the .NET Framework version.
4.
Select the Class Library template.
5.
Check Create Directory for Solution if it isn’t already checked. When working with exten-
sions, creating a solution directory provides a place for putting solution-level objects.
6.
Type Calcs in the Name field and click OK. Visual Studio creates a class library project for you.
7.
Right-click 
Class1.vb
in Solution Explorer and choose Rename from the context menu. 
Visual Studio makes the filename editable.