C#datagridView中嵌套控件

                    string StrSql = "exec proc_PriceReport '" + dgvOrderList.Rows[e.RowIndex].Cells[1].Value.ToString() + "'";
                    dt = DbHelper.DbHelperSQL.DataQuery(StrSql).Tables[0];
                    DataGridViewButtonColumn btnSave = new DataGridViewButtonColumn();
                    //增加按钮列：保存
                    btnSave.UseColumnTextForButtonValue = true;
                    btnSave.Width = 50;
                    btnSave.HeaderText = "------";
                    btnSave.Name = "btnWrite";
                    btnSave.Text = "保存";
                    //增加按钮列：打开图纸
                    DataGridViewButtonColumn btnOpen = new DataGridViewButtonColumn();

                    btnOpen.UseColumnTextForButtonValue = true;
                    btnOpen.Width = 50;
                    btnOpen.HeaderText = "----------";
                    btnOpen.Name = "btnOpen";
                    btnOpen.Text = "    打开图纸    ";
                    btnOpen.Width = 100;
                    
                   
                    this.dgvPartsList.DataSource = dt;
                    //判断是否存在该列，存在则移除，避免了每次增加列时出现多个按钮列
                    if (this.dgvPartsList.Columns.Contains("btnWrite") == true)
                        this.dgvPartsList.Columns.Remove("btnWrite");
                    if (this.dgvPartsList.Columns.Contains("btnOpen") == true)
                        this.dgvPartsList.Columns.Remove("btnOpen");

                        this.dgvPartsList.Columns.Add(btnSave);
                        this.dgvPartsList.Columns.Add(btnOpen);