Attach form window to another window in C#

by

Here is a working example. The hosting app is a simple WinForms application with a blank form (not included here), while the “guest app” has a main form (code behind included below) with some controls, including a test button to display a message after changing the guest form’s parent.

The usual caveats linked to in the OP’s question apply to this, too.

public partial class GuestForm: Form
{
  [DllImport("user32.dll")]
  public static extern int SetWindowLong(IntPtr hWnd, int nIndex, int dwNewLong);

  [DllImport("user32.dll")]
  public static extern int GetWindowLong(IntPtr hWnd, int nIndex);

  [DllImport("user32.dll", SetLastError = true)]
  private static extern IntPtr SetParent(IntPtr hWndChild, IntPtr hWndNewParent);

  public static int GWL_STYLE = -16;
  public static int WS_CHILD = 0x40000000; 

  public GuestForm()
  {
    InitializeComponent();
  }

  private void button1_Click(object sender, EventArgs e)
  {
    MessageBox.Show("done");
  }

  private void button2_Click(object sender, EventArgs e)
  {
    Process hostProcess = Process.GetProcessesByName("HostFormApp").FirstOrDefault();
    if (hostProcess != null)
    {
      Hide();
      FormBorderStyle = FormBorderStyle.None;
      SetBounds(0, 0, 0, 0, BoundsSpecified.Location);

      IntPtr hostHandle = hostProcess.MainWindowHandle;
      IntPtr guestHandle = this.Handle;
      SetWindowLong(guestHandle, GWL_STYLE, GetWindowLong(guestHandle, GWL_STYLE) | WS_CHILD);
      SetParent(guestHandle, hostHandle);

      Show();
    }
  }
}

More Related Contents:

  1. Move window when external application’s window moves
  2. Automating the InvokeRequired code pattern
  3. Invoke(Delegate)
  4. How to deal with files with a name longer than 259 characters?
  5. Cross-thread operation not valid [duplicate]
  6. Passing strings from C# to C++ DLL and back — minimal example
  7. Capture a keyboard keypress in the background
  8. WinForm UI Validation
  9. C# winforms combobox dynamic autocomplete
  10. Global hotkey in console application
  11. Task parallel library replacement for BackgroundWorker?
  12. FTPS (FTP over SSL) in C#
  13. How to set Z-order of a Control using WinForms
  14. Drawing glitches when using CreateGraphics rather than Paint event handler for custom drawing
  15. How do I pinvoke to GetWindowLongPtr and SetWindowLongPtr on 32-bit platforms?
  16. How to draw shapes in WinForms [duplicate]
  17. DataGridView checkbox column – value and functionality
  18. Detecting if paste event occurred inside a rich text box
  19. How do I capture Keys.F1 regardless of the focused control on a form?
  20. How to programmatically mouse move,click,right click and keypress, etc. in winform and wpf?
  21. Rich Text Box how to highlight text block
  22. Add multiple images in the email body (inline)using c# windows application
  23. Rows cannot be programmatically added to the datagridview’s row collection when the control is data-bound
  24. How to change ListBox selection background color?
  25. Resize Controls with Form Resize
  26. How to setup the starting form of a winforms project in Visual Studio 2010
  27. Make a form’s background transparent
  28. Prevent Winforms Designer from Generating Property Values for Inherited Controls
  29. Region.IsVisible(PointF) has very slow performance for large floating point values
  30. Prevent users from resizing the window/form size

Leave a Comment