DOCUMENT:Q255279  11-SEP-2001  [foxpro]
TITLE   :HOWTO: Create a COM DLL with Visual FoxPro that Prints Screen Im
PRODUCT :Microsoft FoxPro
PROD/VER:WINDOWS:6.0
OPER/SYS:
KEYWORDS:kbprint kbCOMt kbPrinting kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet

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The information in this article applies to:

 - Microsoft Visual FoxPro for Windows, version 6.0 
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SUMMARY
=======

This article demonstrates, by example, the general ease with which Component
Object Model (COM) DLLs can be created within Microsoft Visual FoxPro 6.0. The
program code contained in this article enables the user to create a useful
example of a simple COM DLL.

MORE INFORMATION
================

In order for the example to be put to use, the host computer must have a
properly installed copy of Microsoft Office for Windows 95 (or higher). The COM
DLL offers the following functionalities:

 - It captures the screen image of the open and active window.

 - An OLE instance of Microsoft Word is created for the purpose of printing the
   captured screen image.

 - The captured screen image is pasted into a Microsoft Word document.

 - The Microsoft Word Document is printed to the computer's default printer.

To create the COM DLL described in this example, perform the following steps:

1. Within Microsoft Visual FoxPro 6.0, create a new project called "olepscrn"
   (without the quotation marks).

2. Add a new program to the olepscrn project, and input the following code:

   *!* Beginning of program code example:
   DEFINE CLASS p_screen AS CUSTOM OLEPUBLIC
       Name = "p_screen"
       ScreenPrinted = .F.
       oWordObj = ""
       PROCEDURE ScreenCapture
           This.ReleaseWord()
           This.ScreenPrinted = .T.
           DECLARE INTEGER keybd_event IN Win32API ;
               INTEGER, INTEGER, INTEGER, INTEGER
           VK_SNAPSHOT = 44
           =keybd_event(VK_SNAPSHOT, 1, 0, 0)
           This.oWordObj=CREATEOBJECT("Word.Application")
           This.oWordObj.Documents.Add
           This.oWordObj.ActiveDocument.PageSetup.Orientation = 1
           WITH This.oWordObj.WordBasic
               .EditPaste
               .FilePrint
               .FileClose(2)
           ENDWITH
           RELEASE keybd_event, vk_snapshot
       ENDPROC
       PROCEDURE ReleaseWord
           IF This.ScreenPrinted
               This.oWordObj.Quit
               This.oWordObj = ""
               This.ScreenPrinted = .F.
           ENDIF
       ENDPROC
       PROCEDURE Destroy
           This.ReleaseWord()
       ENDPROC
   ENDDEFINE
   *!* End of program code example:

3. Save the program as "p_screen" (without the quotation marks).

4. On the Project Manager, select the Build button, and choose Single-threaded
   COM server (DLL) in Visual FoxPro 6.0 with SP3, or choose Build COM DLL in
   Visual FoxPro 6.0.

5. From the Command window, you can use the DLL by entering the following three
   commands:

   1. This command creates an object reference to the DLL and loads it into
      memory:

   oPScreen = CREATEOBJECT("olepscrn.p_screen")

   2. This command executes the Print Screen:

   oPScreen.ScreenCapture()

   3. This third and final command removes the DLL from memory. When the object
      is released, the instance of Microsoft Word that it created releases as
      well:

   RELEASE oPScreen

REFERENCES
==========

For additional information about programmatic screen capturing, click the
article number below to view the article in the Microsoft Knowledge Base:

   Q153003 How To Perform a Screen Capture Programmatically

For additional information about COM and VFP 6.0, click the article number below
to view the article in the Microsoft Knowledge Base:

   Q188709 Vfpcom.exe Using COM Language Enhancements in VFP 6.0

For more information about Creating Automation Servers, search for Extending
Applications, and then Adding OLE in Visual FoxPro Help.

Additional query words:

======================================================================
Keywords          : kbprint kbCOMt kbPrinting kbvfp600 kbGrpDSFox kbDSupport kbCodeSnippet 
Technology        : kbVFPsearch kbAudDeveloper kbVFP600
Version           : WINDOWS:6.0
Issue type        : kbhowto

=============================================================================

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Copyright Microsoft Corporation 2001.