public static extern bool UpdateLayeredWindow(IntPtr hwnd
, IntPtr hdcDst
, ref POINT pptDst
, ref SIZE psize
, IntPtr hdcSrc
, ref POINT pptSrc
, uint crKey
, [In] ref BLENDFUNCTION pblend
, uint dwFlags
);
protected void RefreshFakeWnd()
{
if (m_bIsRefreshing)
return;
if (!User32Dll.IsWindow(m_FakeWndHandle))
return;
m_bIsRefreshing = true;
POINT ptSrc = new POINT(0, 0);
POINT ptWinPos = new POINT(this.Left, this.Top);
SIZE szWin = new SIZE(m_BgImg.Width, m_BgImg.Height);
byte biAlpha = 0xFF;
BLENDFUNCTION stBlend = new BLENDFUNCTION(BlendOp.AC_SRC_OVER, 0, biAlpha, BlendOp.AC_SRC_ALPHA);
IntPtr hDC = User32Dll.GetDC(m_FakeWndHandle);
if (hDC == IntPtr.Zero)
{
m_bIsRefreshing = false;
Debug.Assert(false, "GetDC failed.");
return;
}
IntPtr hdcMemory = GDI32Dll.CreateCompatibleDC(hDC);
int nBytesPerLine = ((m_BgImg.Width * 32 + 31) & (~31)) >> 3;
BITMAPINFOHEADER stBmpInfoHeader = new BITMAPINFOHEADER();
stBmpInfoHeader.Init();
stBmpInfoHeader.biWidth = m_BgImg.Width;
stBmpInfoHeader.biHeight = m_BgImg.Height;
stBmpInfoHeader.biPlanes = 1;
stBmpInfoHeader.biBitCount = 32;
stBmpInfoHeader.biCompression = CompressionType.BI_RGB;
stBmpInfoHeader.biClrUsed = 0;
stBmpInfoHeader.biSizeImage = (uint)(nBytesPerLine * m_BgImg.Height);
IntPtr pvBits = IntPtr.Zero;
IntPtr hbmpMem = GDI32Dll.CreateDIBSection(hDC
, ref stBmpInfoHeader
, DIBColorTableIdentifier.DIB_RGB_COLORS
, out pvBits
, IntPtr.Zero
, 0
);
Debug.Assert(hbmpMem != IntPtr.Zero, "CreateDIBSection failed.");
if (hbmpMem != null)
{
IntPtr hbmpOld = GDI32Dll.SelectObject(hdcMemory, hbmpMem);
Graphics graphic = Graphics.FromHdcInternal(hdcMemory);
graphic.DrawImage(m_BgImg, 0, 0, m_BgImg.Width, m_BgImg.Height);
foreach (Control ctrl in this.Controls)
{
if (!ctrl.Visible)
continue;
using (Bitmap bmp = new Bitmap(ctrl.Width, ctrl.Height))
{
Rectangle rect = new Rectangle(0, 0, ctrl.Width, ctrl.Height);
ctrl.DrawToBitmap(bmp, rect);
graphic.DrawImage(bmp, ctrl.Left, ctrl.Top, ctrl.Width, ctrl.Height);
}
}
GUITHREADINFO stGuiThreadInfo = new GUITHREADINFO();
stGuiThreadInfo.Init();
if (User32Dll.GetGUIThreadInfo(Kernal32Dll.GetCurrentThreadId(), ref stGuiThreadInfo))
{
if (User32Dll.IsWindow(stGuiThreadInfo.hwndCaret))
{
int height = stGuiThreadInfo.rcCaret.Bottom - stGuiThreadInfo.rcCaret.Top;
POINT ptCaret = new POINT(stGuiThreadInfo.rcCaret.Left, stGuiThreadInfo.rcCaret.Top);
User32Dll.ClientToScreen(stGuiThreadInfo.hwndCaret, ref ptCaret);
User32Dll.ScreenToClient(this.Handle, ref ptCaret);
graphic.DrawLine(new Pen(new SolidBrush(Color.Black))
, ptCaret.X
, ptCaret.Y
, ptCaret.X
, ptCaret.Y + height
);
}
}
User32Dll.UpdateLayeredWindow(m_FakeWndHandle
, hDC
, ref ptWinPos
, ref szWin
, hdcMemory
, ref ptSrc
, 0
, ref stBlend
, UpdateLayerWindowParameter.ULW_ALPHA
);
graphic.Dispose();
GDI32Dll.SelectObject(hbmpMem, hbmpOld);
GDI32Dll.DeleteObject(hbmpMem);
}
GDI32Dll.DeleteDC(hdcMemory);
GDI32Dll.DeleteDC(hDC);
m_bIsRefreshing = false;
}
