Accessing the Visual FoxPro API

If Visual FoxPro does not include the features you require for your application already, you can extend its capabilities by creating a Microsoft ActiveX control (.ocx file) or library (.fll file) specific to Visual FoxPro.

In This Section

• Library or ActiveX Object Creation
  You can extend the capabilities of Visual FoxPro by creating programs that accomplish tasks required by your application.
• Adding Visual FoxPro API Calls
  To integrate your program with Visual FoxPro, you can call Visual FoxPro API routines.
• Passing and Reception of Parameters
  When your program is called from Visual FoxPro, it can receive parameters.
• Return of a Value to Visual FoxPro
  The method you use to return a value from your program to Visual FoxPro depends on whether you are creating a Microsoft ActiveX control or an FLL library.
• Passing of Parameters to Visual FoxPro API Functions
  Often the Visual FoxPro API routines will require parameters of a particular Visual FoxPro data structure.
• Access to Visual FoxPro Variables and Fields
  You can access Visual FoxPro variables or field values in your ActiveX control or FLL function, either to read them or to set them.
• Managing Memory
  The Visual FoxPro API provides direct access to the Visual FoxPro dynamic memory manager.
• Building and Debugging Libraries and ActiveX Controls
  After creating a project, you are ready to build and debug it.

Related Sections

• Accessing APIs
  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 — Microsoft ActiveX controls or dynamic-link libraries (DLLs).
• Extending Visual FoxPro with External Libraries
  You can add 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.
• API Library Construction
  Reference material covering API Library routines, system events, and key codes.