C#

public class FixedListView : ListView
{
    private const int WM_LBUTTONUP = 0x0202;

    protected override void WndProc(ref Message m)
    {
        if (m.Msg == WM_LBUTTONUP)
        {
            // adjusting as X and Y are 16 bits each of LParam
            Point point = new Point(((int)m.LParam) & 0x0000FFFF, (int)m.LParam >> 16);
            OnMouseUp(new MouseEventArgs(MouseButtons.Left, 1, point.X, point.Y, 0));
            return;
        }
        base.WndProc(ref m);
    }
}

public class CustomListView : ListView
{
	public CustomListView()
	{
		InitializeComponent();
	}

	bool fakeMouseUp = false;
	bool mouseDownOnItem = false;

	protected override void OnMouseDown( MouseEventArgs e )
	{
		// if we're not on an item or subitem, we will get OnMouseUp immediately
		mouseDownOnItem = HitTest( e.Location ).Item != null;

		Debug.WriteLine( "OnMouseDown" );

		base.OnMouseDown( e );
	}

	protected override void OnMouseUp( MouseEventArgs e )
	{
		if( mouseDownOnItem || fakeMouseUp )
		{
			Debug.WriteLine( "OnMouseUp" );

			mouseDownOnItem = false;
			fakeMouseUp = false;

			base.OnMouseUp( e );
		}
	}

	protected override void WndProc( ref Message m )
	{
		if( !mouseDownOnItem && m.Msg == 0x0202 /*WM_LBUTTONUP*/ )
		{
			// send a fake MouseUp event
			fakeMouseUp = true;
			Point point = new Point( ((int) m.LParam) & 0x0000FFFF, (int) m.LParam >> 16 );
			OnMouseUp( new MouseEventArgs( MouseButtons.Left, 1, point.X, point.Y, 0 ) );
		}

		base.WndProc( ref m );
	}
}

public FormA()
{
    IntPtr handle = Handle;
    // From this point onwards, Handle is valid so you can use Invoke, BeginInvoke, InvokeRequired etc...
} 

Yanshof wrote:

does this collection cleaning can cause somehow the GC to run ?