private void btnSearch_Click(object sender, EventArgs e)
        {
            //获取待搜索的信息
            string name = txtClassName.Text.Trim();
            //连接Sql server 数据库
            SqlConnection con = new SqlConnection("Data Source=.;Initial Catalog=gsInfo;Integrated Security=True");
            string sql = String.Format("select * from T_classInfo where 班级名称='{0}' ", name);
            try
            {
                con.Open();//打开与数据库的链接
                SqlCommand cmd = new SqlCommand(sql, con);//定义Command对象
                SqlDataReader reader = cmd.ExecuteReader();
                //string className = reader.GetString(reader.GetOrdinal("班级名称"));
                if (reader.Read())
                {
                    string classShortName = reader.GetString(reader.GetOrdinal("班级简称"));
                    string grade = reader.GetString(reader.GetOrdinal("年级"));
                    string classNo = reader.GetString(reader.GetOrdinal("班级编号"));
                    string classNumber = reader.GetString(reader.GetOrdinal("人数"));
                    string teacher = reader.GetString(reader.GetOrdinal("辅导员"));
                    txbClassName.Text = name;
                    txbShortName.Text = classShortName;
                    txbGrade.Text = grade;
                    txbClassNumber.Text = classNo;
                    txbNo.Text = classNumber;
                    txbTeacher.Text = teacher;
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
            finally
            {
                con.Close();
            }