dgvFromRoomKat.Columns["idRoomType"].Visible = false;

            column = new DataGridViewComboBoxColumn();
            column.DisplayMember = "RoomTypeName";
            column.ValueMember = "idRoomType";
            column.DataSource = ClassInitEEFSet.myDs.Tables["SprRoomType"];
            column.DataPropertyName = "RoomTypeName";
            column.Name = "idRoomType";
            column.HeaderText = "Категория";
            column.ReadOnly = false;
            column.Width = 250;
            dgvFromRoomKat.Columns.Add(column);