C#向数据库表中插入信息。。求不吐槽命名规范

Question

 if (textBox5.Text.Trim() == string.Empty || textBox4.Text.Trim() == string.Empty)
            {
                MessageBox.Show("请输入课程号和课程名！");
            }
            else {
                string consqlserver = "server = .;Initial Catalog=Students;integrated security=true";
                SqlConnection conn = new SqlConnection(consqlserver);
                string sql = "insert into 课程(课程号，课程名) values('" + textBox5.Text.Trim() + "','" + textBox4.Text.Trim() + "')";
                conn.Open();
                string sql1 = "select * from 课程 where 课程名 ='" + textBox4.Text + "' or 课程号 ='" + textBox5.Text + "'";
                string sql2 = "update 课程 set " +
                    " 课程号 = '" + textBox5.Text + "'," +
                    " 课程名 = '" + textBox4.Text + "', where 课程名 = '" + textBox4.Text + "' or 课程号 = '" + textBox5.Text + "'";
                SqlCommand mysqlcommand = conn.CreateCommand();
                mysqlcommand.CommandText = sql;
                SqlDataReader myread = mysqlcommand.ExecuteReader();

                if (myread.HasRows)
                {
                    DialogResult result = MessageBox.Show("已存在课程，是否在原有信息上面更新信息？","Attention!",MessageBoxButtons.OKCancel, MessageBoxIcon.Information,MessageBoxDefaultButton.Button3);
                    switch (result)
                    {
                        case DialogResult.OK:
                            conn.Close();
                            conn.Open();
                            mysqlcommand.CommandText = sql2;
                            mysqlcommand.ExecuteNonQuery();

                            conn.Close();

                            MessageBox.Show("已完成课程的更新！");
                            break;
                        case DialogResult.Cancel:
                            MessageBox.Show("未做任何修改！");
                            break;
                    }
                }
                else
                {
                    conn.Close();
                    conn.Open();
                    mysqlcommand.CommandText = sql;
                    mysqlcommand.ExecuteNonQuery();

                    conn.Close();
                    MessageBox.Show("添加该新课程成功！");
                }
            }
            this.Hide();
            Frmindex frmindex = new Frmindex();
            frmindex.ShowDialog();
        }

Answer 1

http://www.cnblogs.com/rainman/archive/2012/03/13/2393975.html