The .NET Compact Framework supports about 28 percent of the namespaces and classes of the full .NET Framework, and is about 8 percent of its size. To keep the size small, only the most important classes and members are supported.
For information about how to use the class library to determine .NET Compact Framework support and versioning, see How to: Use the Class Library for the .NET Compact Framework.
The .NET Compact Framework does not support the following technologies:
J# and JSL development
The .NET Compact Framework does not support code access security in version 1.0 and 2.0, but it is planned for a future release.
The following namespaces and classes are available only in the .NET Compact Framework.
Mobile Direct3D Programming
How to: Use the MessageWindow Class
How to: Use a DocumentList Control
How to: Use the HardwareButton Component
How to: Use the InputPanel Component
How to: Set Pocket PC Input Methods
How to: Send a Notification
How to: Set Smartphone Input Modes
How to: Make an Infrared File Transfer
What's New in SQL Server Compact Edition