關於視窗的一點心得

/// how to capture window @ mouse?
    // capture the window under the cursor's position
    IntPtr hWnd = Win32.WindowFromPoint(Cursor.Position);
    // handle
    _textBoxHandle.Text = string.Format("{0}", hWnd.ToInt32().ToString());

    // class
    _textBoxClass.Text = this.GetClassName(hWnd);

    // caption
    _textBoxText.Text = this.GetWindowText(hWnd);

    Win32.Rect rc = new Win32.Rect();
    Win32.GetWindowRect(hWnd, ref rc);
       
    // rect
    _textBoxRect.Text = string.Format("[{0} x {1}], ({2},{3})-({4},{5})", rc.right - rc.left, rc.bottom - rc.top, rc.left, rc.top, rc.right, rc.bottom);

/// 自己的 Root Form Handler
if (hWnd == IntPtr.Zero)
{
}

/// 如何抓 window image?

    // capture that window
    Image image = ScreenCapturing.GetWindowCaptureAsBitmap(handle);

    // fire our image read event, which the main window will display for us
    this.OnImageReadyForDisplay(image);

/// 如何等候 Image 已經畫好再做事？

    public event DisplayImageEventHandler ImageReadyForDisplay;
    ImageReadyForDisplay += new DisplayImageEventHandler(this.DisplayImage);
    if (ImageReadyForDisplay != null)
        ImageReadyForDisplay(image, false, PictureBoxSizeMode.CenterImage);

/// 如何抓例外
    try
    {
        if (this.ImageReadyForDisplay != null)
            this.ImageReadyForDisplay(image, false, PictureBoxSizeMode.CenterImage);
    }
    catch(Exception ex)
    {
        Debug.WriteLine(ex);
    }
           
public class WindowHighlighter
{               
    public static void Highlight(IntPtr hWnd)
    {
        const float penWidth = 3;
        Win32.Rect rc = new Win32.Rect();
        Win32.GetWindowRect(hWnd, ref rc);

        IntPtr hDC = Win32.GetWindowDC(hWnd);
        if (hDC != IntPtr.Zero)
        {
            using (Pen pen = new Pen(Color.Black, penWidth))
            {
                using (Graphics g = Graphics.FromHdc(hDC))
                {
                    g.DrawRectangle(pen, 0, 0, rc.right - rc.left - (int)penWidth, rc.bottom - rc.top - (int)penWidth);
                }
            }
        }
        Win32.ReleaseDC(hWnd, hDC);
    }

    public static void Refresh(IntPtr hWnd)
    {
        Win32.InvalidateRect(hWnd, IntPtr.Zero, 1);
        Win32.UpdateWindow(hWnd);
        Win32.RedrawWindow(hWnd, IntPtr.Zero, IntPtr.Zero, Win32.RDW_FRAME | Win32.RDW_INVALIDATE | Win32.RDW_UPDATENOW | Win32.RDW_ALLCHILDREN);       
    }
}