How to suppress KeyDown event in WinForms GridGroupingControl?

// form
// Trigger the required event.
gridGroupingControl1.TableControlCurrentCellKeyDown += gridGroupingControl1_TableControlCurrentCellKeyDown;
 
void gridGroupingControl1_TableControlCurrentCellKeyDown(object sender, GridTableControlKeyEventArgs e)
{
      e.Inner.SuppressKeyPress = true;
}
protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
   Keys keyCode = keyData & Keys.KeyCode;
   switch (keyCode)
   {
      case Keys.Down: MessageBox.Show("KeyDown Event suppressed");
              break;
      case Keys.Up: MessageBox.Show("KeyDown Event suppressed");
              break;
      case Keys.Right: MessageBox.Show("KeyDown Event suppressed");
              break;
      case Keys.Left: MessageBox.Show("KeyDown Event suppressed");
              break;
      case Keys.PageUp: MessageBox.Show("KeyDown Event suppressed");
              break;
      case Keys.PageDown: MessageBox.Show("KeyDown Event suppressed");
              break; 
  }
   return base.ProcessCmdKey(ref msg, keyData);
}

' form()
' Trigger the required event. 
Private gridGroupingControl1.TableControlCurrentCellKeyDown += AddressOf gridGroupingControl1_TableControlCurrentCellKeyDown
Private Sub gridGroupingControl1_TableControlCurrentCellKeyDown(ByVal sender As Object, ByVal e As GridTableControlKeyEventArgs)
      e.Inner.SuppressKeyPress = True
   End If
End Sub
Protected Overrides Function ProcessCmdKey(ByRef msg As Message, ByVal keyData As Keys) As Boolean
   Dim keyCode As Keys = keyData And Keys.KeyCode
   Select Case keyCode
       Case Keys.Down MessageBox.Show("KeyDown Event suppressed")
                break
       Case Keys.Up MessageBox.Show("KeyDown Event suppressed")
                break
       Case Keys.Right MessageBox.Show("KeyDown Event suppressed")
                break
       Case Keys.Left MessageBox.Show("KeyDown Event suppressed")
                break
       Case Keys.PageUp MessageBox.Show("KeyDown Event suppressed")
                break
       Case Keys.PageDown MessageBox.Show("KeyDown Event suppressed")
                break
   End Select
   Return MyBase.ProcessCmdKey(msg, keyData)
End Function