c#保存数据 使用事务和参数化 标准

SqlConnection cn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["wishConnectionString"].ConnectionString);
            SqlTransaction ta = null;
            try
            {
                cn.Open();
                ta = cn.BeginTransaction();
                SqlCommand cmd = new SqlCommand("insert into tbl_Question(course,question,point,ken,type,[delete]) values(@course,@question,@point,@ken,@type,@delete);select @id = scope_identity()", cn);
                cmd.Transaction = ta;
                cmd.Parameters.Add("@id", SqlDbType.Int).Direction = ParameterDirection.Output;
                cmd.Parameters.AddWithValue("@course", Request.QueryString["course"]);
                cmd.Parameters.AddWithValue("@question", txtQuestion.Text.Trim());
                cmd.Parameters.AddWithValue("@point", dropPoint.SelectedValue);
                cmd.Parameters.AddWithValue("@ken", dropKen.SelectedValue);
                cmd.Parameters.AddWithValue("@type", Request.QueryString["type"]);
                cmd.Parameters.AddWithValue("@delete", 0);

                cmd.ExecuteNonQuery();
                int id = (int)cmd.Parameters["@id"].Value;
                cmd.Parameters.Clear();
                cmd.CommandText = "insert into tbl_Answer([ID_Question], [Option], [iskey]) values(@id_Question, @option, @iskey)";
                for (int i = 1; i <= 4; i++)
                {
                    cmd.Parameters.AddWithValue("@id_Question", id);
                    cmd.Parameters.AddWithValue("@option", (Form.FindControl("txtAnswer" + i.ToString()) as TextBox).Text);
                    cmd.Parameters.AddWithValue("@iskey", (Form.FindControl("chkKey" + i.ToString()) as CheckBox).Checked);
                    cmd.ExecuteNonQuery();
                    cmd.Parameters.Clear();
                }
                ta.Commit();
                lblMessage.Text = "添加成功!";
            }
            catch (Exception ex)
            {
                try
                {
                    ta.Rollback();
                }
                catch (Exception exx)
                {
                    lblMessage.Text = exx.Message;
                }
                lblMessage.Text = ex.Message;
            }
            finally
            {
                cn.Close();
            }