Get Window Pixel

From:
=?Utf-8?B?U2F1bDc3NQ==?= <Saul775@discussions.microsoft.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Thu, 8 Mar 2007 13:03:55 -0800
Message-ID:
<BEDFBA2B-656C-41C6-96AD-74569F1CF28E@microsoft.com>
Hello:

I have a pixel on the screen that I'm trying to obtain the color. The pixel
is found in a static control, which is a class derived from CStatic.

class CReflectColorWnd : public CStatic

I've tried many ways to obtain the pixel, but I cannot attain the COLORREF
of the pixel. I'm wondering if anyone would be kind enough to assist me.

I've tried the following in the paint handler.

void CReflectColorWnd::OnPaint()
{
  CStatic::OnPaint(); // Call original paint

  CClientDC dc(this);

  CBitmap bm;
  bm.CreateCompatibleBitmap(&dc, 100, 100);

  CDC memDC;
  memDC.CreateCompatibleDC(&dc);

  CBitmap *pOrigBM = memDC.SelectObject(&bm);

  this->SendMessage(WM_PRINT, (WPARAM)memDC.GetSafeHdc(), (LPARAM)PRF_CLIENT);

  COLORREF cr = memDC.GetPixel(5, 5);

  memDC.SelectObject(pOrigBM);

  .. // Do something with the color obtained
}

This code, unfortunately, does not seem to work. I've been reading some
articles in the Newsgroups, and they indicate I should just obtain a
CClientDC to the window and just call .GetPixel(). I -- by experience --
perceive this to be a flaw, but I could be wrong. A DC doesn't take the
screen pixels to initialize the DC, does it? That said, I've tried it their
way and still have yet to obtain the pixel colors. Any ideas of what I can
alter or any other methods of obtaining the pixel? Thank you, all.

Saul775

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