If your application has requirements that cannot be met by the features already built into Visual FoxPro, you can extend the program by taking advantage of external libraries such as Microsoft ActiveX controls or dynamic-link libraries (DLLs). Using external libraries, you can add all kinds of objects to your application, from enhanced text boxes to calendars and other full-featured applications, and you can take advantage of the functionality offered by other programs (including Microsoft Windows) through their application programming interfaces (APIs).

In This Section

Extending Visual FoxPro with External Libraries: Explains that you can add Microsoft ActiveX controls (.ocx files) to your application easily, which provides you with new objects to use in forms, to subclass, and to manage the way you work with native Visual FoxPro controls. In addition, you can link to an external library, such as a DLL, and call the library's functions to use in your own programs.

Accessing the Visual FoxPro API: If an external library is not available to suit your needs, you can write your own Microsoft ActiveX control or Visual FoxPro-specific dynamic-link library (.fll file). By calling the functions available in the Visual FoxPro API, you can create controls or libraries that are tightly integrated with and optimized for use in Visual FoxPro.

Related Sections

Programming in Visual FoxPro: Visual FoxPro is a powerful interactive data management tool, but you also can access the full power of Visual FoxPro by creating applications. Understanding object-oriented programming techniques and the event-driven model can maximize your programming productivity.

How to: Create Programs: Explains the two ways to create a Visual FoxPro program, which is a text file containing a series of commands.

Object-Oriented Programming: With object-oriented programming, you can create self-contained application components that respond to user actions and to the system and which can be easily maintained and reused.

Optimizing Applications: Describes ways to optimize the performance of your stable, running application by making your application smaller and faster.