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Q153003: How To Perform a Screen Capture Programmatically

Article: Q153003
Product(s): Microsoft FoxPro
Version(s): WINDOWS:3.0,3.0b,6.0
Operating System(s): 
Keyword(s): kb3rdparty kbvfp300 kbvfp600
Last Modified: 26-OCT-2000

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The information in this article applies to:

- Microsoft Visual FoxPro for Windows, versions 3.0, 3.0b, 6.0 
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SUMMARY
=======

It is not possible to use the KEYBOARD command in FoxPro to stuff the keyboard
buffer with PrintScrn or Alt+PrintScrn to copy the whole screen or the active
window to the clipboard. This article describes how you can call the Win32 API
function, keybd_event, to get this functionality under Windows 95 and Windows
NT. This functionality, however, is not available under Windows 3.1 or Windows
for Workgroups since the Win32s subsystem does not contain these API functions.

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

The following commands register the keybd_event function and set up a variable
that will be passed each time to the function:

     DECLARE INTEGER keybd_event IN Win32API ;
        INTEGER, INTEGER, INTEGER, INTEGER
     VK_SNAPSHOT = 44    && from the winuser.h
     VK_LMENU = 164
     KEYEVENTF_KEYUP = 2
     KEYEVENTF_EXTENDEDKEY = 1

The following commands copy the full windows desktop to the clipboard (the
equivalent of PrintScrn):

  DOEVENTS
  keybd_event(VK_SNAPSHOT, 1, 0, 0 )
  keybd_event(VK_SNAPSHOT, 1, KEYEVENTF_KEYUP, 0 )
  DOEVENTS

The following commands copy the active application window to the clipboard (the
equivalent of ALT+PrintScrn):

  DOEVENTS
  keybd_event( VK_LMENU,    0, KEYEVENTF_EXTENDEDKEY, 0 )  && key down
  keybd_event( VK_SNAPSHOT, 0, KEYEVENTF_EXTENDEDKEY, 0 )
  keybd_event( VK_SNAPSHOT, 0, KEYEVENTF_EXTENDEDKEY + KEYEVENTF_KEYUP, 0 )
  keybd_event( VK_LMENU,    0, KEYEVENTF_EXTENDEDKEY + KEYEVENTF_KEYUP, 0 )  
  DOEVENTS

Additional query words: VFoxWin

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Keywords          : kb3rdparty kbvfp300 kbvfp600 
Technology        : kbVFPsearch kbAudDeveloper kbVFP300 kbVFP300b kbVFP600
Version           : WINDOWS:3.0,3.0b,6.0

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