How to retrieve the column header text of a clicked cell in the WinForms GridGroupingControl?

void gridGroupingControl1_TableControlCellClick(object sender, GridTableControlCellClickEventArgs e)
{
  int field = e.TableControl.TableDescriptor.ColIndexToField(e.Inner.ColIndex);
  MessageBox.Show(e.TableControl.TableDescriptor.Columns[field].HeaderText);
}

Private Sub gridGroupingControl1_TableControlCellClick(ByVal sender As Object, ByVal e As GridTableControlCellClickEventArgs)
   Dim field As Integer = e.TableControl.TableDescriptor.ColIndexToField(e.Inner.ColIndex)
   MessageBox.Show(e.TableControl.TableDescriptor.Columns(field).HeaderText)
End Sub