public static IntPtr Capture(IntPtr windowHandle, int x, int y, int width, int height)
{
if (width < 0)
{
throw new ArgumentOutOfRangeException(nameof(width));
}
if (height < 0)
{
throw new ArgumentOutOfRangeException(nameof(height));
}
if (width == 0 || height == 0)
{
return(IntPtr.Zero);
}
IntPtr hSource = Window.GetWindowDC(windowHandle);
IntPtr hMemory = GDI.CreateCompatibleDC(hSource);
IntPtr hBitmap = GDI.CreateCompatibleBitmap(hSource, width, height);
IntPtr hPrimaryBitmap = GDI.SelectObject(hMemory, hBitmap);
GDI.BitBlt(hMemory, 0, 0, width, height, hSource, x, y, GDI.RasterOperationCodes.SRCCOPY);
GDI.SelectObject(hMemory, hPrimaryBitmap);
GDI.DeleteDC(hMemory);
Window.ReleaseDC(windowHandle, hSource);
return(hBitmap);
}
public void UpdateView()
{
if ((FUpdateCount == 0) && IsHandleCreated)
{
if (FMemDC != IntPtr.Zero)
{
GDI.DeleteDC(FMemDC);
}
FMemDC = (IntPtr)GDI.CreateCompatibleDC(FDC);
int vViewWidth = GetViewWidth();
int vViewHeight = GetViewHeight();
IntPtr vBitmap = (IntPtr)GDI.CreateCompatibleBitmap(FDC, vViewWidth, vViewHeight);
GDI.SelectObject(FMemDC, vBitmap);
try
{
using (HCCanvas vDataBmpCanvas = new HCCanvas(FMemDC))
{
// 控件背景
vDataBmpCanvas.Brush.Color = Color.White;// $00E7BE9F;
vDataBmpCanvas.FillRect(new RECT(0, 0, vViewWidth, vViewHeight));
PaintInfo vPaintInfo = new PaintInfo();
try
{
FData.PaintData(this.Padding.Left - FHScrollBar.Position, // 当前页数据要绘制到的Left
this.Padding.Top, // 当前页数据要绘制到的Top
this.Width - FHScrollBar.Position - this.Padding.Right,
this.Padding.Top + FData.Height, // 当前页数据要绘制的Bottom
this.Padding.Top, // 界面呈现当前页数据的Top位置
this.Height - FHScrollBar.Height, // 界面呈现当前页数据Bottom位置
FVScrollBar.Position, // 指定从哪个位置开始的数据绘制到页数据起始位置
vDataBmpCanvas,
vPaintInfo);
for (int i = 0; i <= vPaintInfo.TopItems.Count - 1; i++) // 绘制顶层Ite
{
vPaintInfo.TopItems[i].PaintTop(vDataBmpCanvas);
}
}
finally
{
vPaintInfo.Dispose();
}
GDI.BitBlt(FDC, 0, 0, vViewWidth, vViewHeight, FMemDC, 0, 0, GDI.SRCCOPY);
}
}
finally
{
GDI.DeleteObject(vBitmap);
}
RECT vRect = new RECT(0, 0, vViewWidth, vViewHeight);
User.InvalidateRect(this.Handle, ref vRect, 0); // 只更新变动区域，防止闪烁，解决BitBlt光标滞留问题
User.UpdateWindow(this.Handle);
}
}
