protected override void OnFormClosing(FormClosingEventArgs e)
 {
     base.OnFormClosing(e);
     _Helper.SelectedRowChanged -= _Helper_SelectedRowChanged;
     _Helper.Disable();
     _Helper = null;
 }
 public Form1()
 {
     InitializeComponent();
     gridControl1.DataSource = CreateTable(20);
     _Helper = new GridRadioGroupColumnHelper(gridView1);
     _Helper.SelectedRowChanged += _Helper_SelectedRowChanged;
 }