Understanding the .NET Compact Framework

Microsoft developed the .NET Compact Framework with one intention in mind: to build applications. By applications, I don't mean drivers, COM components, ActiveX controls, Today screen plug-ins, or anything else that might get you called geek by other kids on the tech playground. I'm talking about applications that display, gather, process, and forward information. You know, those applications that give users a reason to carry a device. While they typically will have an interface, they don't have to have one. The data that they are working with might be local, remote, or some combination of the two.

The .NET Compact Framework simplifies application development on smart devices. A smart device is Microsoft's generic category name for any device that has, well, smarts. Currently this includes the Pocket PC, Pocket PC 2002, Pocket PC Phone Edition, Smartphone, and other devices running Windows CE .NET 4.1 or later.

Note

Presently, you can't use the .NET Compact Framework to develop applications that target the Smartphone. Microsoft has stated that they will provide a Smartphone SDK in 2003. This SDK, which will install on top of Visual Studio .NET, will include a Smartphone emulator.

You will need Visual Studio .NET 2003 to build applications that target the .NET Compact Framework. VS .NET 2003 includes Smart Device Extensions, or SDE. It's SDE that enables you to create applications for the .NET Compact Framework. You can build applications using either Visual C# .NET, Visual Basic .NET, or both.

The .NET Compact Framework has two main components: the common language runtime, or CLR, and the .NET Compact Framework class library.

The CLR is the foundation of the .NET Compact Framework. It's responsible for managing code at execution time, providing core services such as memory management and thread management, while enforcing code safety and accuracy. Code that targets the runtime is known as managed code; code that doesn't target the runtime, as is the case with eMbedded Visual C++, is known as unmanaged, or native, code.

The .NET Compact Framework class library is a collection of reusable classes that you can use to quickly and easily develop applications. This framework was designed with porting in mind, whether that is to Microsoft or other third-party platforms. What does this mean to you? Simply that the coding techniques and the applications you create today to run on a Pocket PC could run on other platforms, such as a cell phone or another vendor's PDA, if a version of the .NET Compact Framework was created for that platform.