The Windows 7 Training Kit for Developers includes several sample applications that can help you get started with creating multitouch applications in managed code (C# or VB), native code or MFC. The managed code and native code samples require Visual Studio 2008 SP1, whereas the MFC samples require Visual Studio 2010 beta or higher.
To see some demo multitouch applications, click the video images below.
The managed code sample is a WPF application with references to the Windows7.Multitouch.dll and Windows7.Multitouch.WPF.dll. Multi-touch events and controls are not available in WPF 3.5; they will be part of WPF 4.0 (or .NET 4.0). These two dlls enable your managed code to work with native Windows 7 multitouch APIs through an interop wrapper. You can get the source code of the interop library here.
The first step is your application is to check if the device is touch capable with code that may look like.
MessageBox.Show("Multitouch is not availible");
If Not Windows7.Multitouch.TouchHandler.DigitizerCapabilities.IsMultiTouchReady Then
MsgBox("Multitouch is not availible")
For more detail, check the completed code at the default install location, e.g. C:\Windows7TrainingKit\Labs\Multitouch - Managed\Source\Ex1-PictureHandling\End\C#
To learn more about Windows 7 multitouch, check online resources below: