How to copy the desktop into an image control

[hennep]

I tried to capture the desktop into an TImage control using this code:

void __fastcall TForm1::FormCreate(TObject *Sender) {
    HANDLE h1, h2;
    long w, h;
    RECT rect;

    GetWindowRect( GetDesktopWindow(), &rect );
    w = rect.right - rect.left;
    h = rect.bottom - rect.top;

    h1 = GetDC( GetDesktopWindow() );
    h2 = GetDC( Image1->Picture->Bitmap->Handle );
    BitBlt( h2, 0, 0, w, h, h1, 0, 0, SRCCOPY );
}

But I definitely don't know what i am doing. Why doesn't it work ?

 

[LastCyborg]

I don't know what are you doing with that code too, but I think you should investigate about Keyboard key that copies the screen into the Clipboard and then copy it to the control.

--- LastCyborg ---

 

[hennep]

hi LastCyborg,

I cannot use the clipboard. The code is part of a screen saver, it would change the contents of the clipboard every time the screensaver was executed.

 

[LastCyborg]

Well, you can save it contents in a temporal identifier, and load the clippboard with the last value after you finish what you are doing.

--- LastCyborg ---

 

[c567591]

What happens with this code you posted?
How is SRCCOPY defined?
Plopping to the clippboard each time would be a bad way to do that.

 

[butthead]

anyone know how to get the screen buffer.

tomcruz.nert

 

[butthead]

http://www.codeproject.com/dialog/screencap.asp

tomcruz.net

 

[hennep]

hi Tom,

Did you get this to work?
The first code snippet on the codeproject page results in a handle to the bitmap. But how would you show the bitmap in a TPicture control or the canvas of a form?

 

[hennep]

I wrote "TPicture", but I meant a TImage.
I just saw that there is such a thing as a TPicture but I've never used it.