private void button6_Click(object sender, EventArgs e)

        {

            int selectedRows = dataGridView2.SelectedRows.Count;

            for (int j = 0; j < selectedRows; j++)

            {

                try

                {

                    if (dataGridView2.Rows[j].Cells["选择"].Value != null)

                    {

                        if (bool.Parse(dataGridView2.Rows[j].Cells["选择"].Value.ToString()) == true)

                        {

                            MessageBox.Show("123");

                            string DElsql = string.Format("Delete From Question Where QuestionID = {0}", Convert.ToInt32(dataGridView2.SelectedRows[0].Cells["题号"].Value));

                            conn.Open();

                            SqlCommand cmd = new SqlCommand(DElsql, conn);

                            cmd.ExecuteNonQuery();

                            conn.Close();

                            dataview();



                        }

                    }

                }

                catch (Exception ex)

                { MessageBox.Show(ex.Message); }

               

            }