HowTo : Close a form in VB/C#(.NET) with an open vectordraw command?

Subject

Summary

How to close a form in VB/C#(.NET) with an open vectordraw command?

Solution

Visual Basic 6.0

You have to add these API declares in a module
Public Declare Function PostMessage Lib "user32" Alias "PostMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
Public Const WM_CLOSE = &H10

Then add these code in Form_QueryUnload event :
    If VDraw.CommandAction.OpenLoops > 0 Then
        Cancel = True
        VDraw.CommandAction.Cancel
        PostMessage Me.hwnd, WM_CLOSE, 0, 0
    End If

VisualC# (.NET)

You have to add these API declares :

      [DllImport("user32.dll", CharSet=CharSet.Auto)]
      public static extern IntPtr SendMessage(IntPtr hWnd, int msg, int wParam, int lParam);
      [DllImport("user32.dll", CharSet=CharSet.Auto)]
      public static extern IntPtr PostMessage(IntPtr hWnd, int msg, int wParam, int lParam);

      const int WM_CLOSE = 0x10;

Then in form closing event put the following code:

    while (vdraw.CommandAction.OpenLoops>0)
   {
        e.Cancel = true;
        vdraw.CommandAction.Cancel();
        PostMessage ( this.Handle, WM_CLOSE, 0, 0 );
   }

Don't forget "using System.Runtime.InteropServices;"