public DGV_ListBox(DataGridView parentDGV, IDGV_ListBoxItem DGV_ListBoxItem)
 {
     _ListBox                 = new ListBox();
     _DGV_ListBoxItem         = DGV_ListBoxItem;
     this._ListBox.Visible    = false;
     this._ListBox.DataSource = DGV_ListBoxItem.Items;
     _parentDGV               = parentDGV;
     _parentDGV.Controls.Add(this._ListBox);
     _parentDGV.CellClick += _parentDGV_CellClick;
     this._ListBox.SelectedIndexChanged += DGV_ListBox_SelectedIndexChanged;
 }
        public void AddDropDownBox(IDGV_ListBoxItem DGV_ListBoxItem)
        {
            DGV_ListBox newDGV_ListBox = new DGV_ListBox(this, DGV_ListBoxItem);

            _DropDownBoxes.Add(newDGV_ListBox);
        }