You can extend the language capabilities of the toolkit by calling procedures included in the Windows CE API. The Windows CE API, a subset of the Microsoft® Win32® API, is a collection of DLLs containing many of the procedures used by Windows-based desktop platforms. You can use these DLLs to accomplish a variety of tasks, such as displaying windows and graphics, managing memory and power, and accessing persistent storage.
The toolkit provides a text file, Winceapi.txt, that contains predefined declarations for many of the Windows CE API procedures commonly used in Visual Basic for Windows CE applications. To use a function, data type, or other element from this file, simply copy it to your project module. In addition, you can view and copy these elements from Winceapi.txt either by loading the file in any text editor or by using the API Viewer application included in the toolkit.
As an alternative to using the predefined declarations included with the toolkit, you can write custom declarations. To write a custom declaration, you must use the Declare statement, which associates a procedure from the Windows CE API with the procedure in your declaration. The following sections detail the process of creating your own declaration.