static void Main(string[] args)
        {
            Console.WriteLine("===RD University!===\n");
            Console.WriteLine("What you want to do?");

            var dataProvider        = new StudentDataProvider();
            var consoleReaderWriter = new ConsoleReaderWriter();
            var printerWriter       = new PrinterWriter();

            var students = dataProvider.GetStudents();

            var input = consoleReaderWriter.Read();

            switch (input)
            {
            case "s":
                students.ToList().ForEach(consoleReaderWriter.Write);
                break;

            case "p":
                students.ToList().ForEach(printerWriter.Write);
                break;
            }

            Console.ReadKey();
        }
        /// <summary>
        /// 查询字符串:
        /// </summary>
        private void GetMajorName()
        {
            ///
            /// 老方法
            ///

            //构造查询字符串

            //string sql = "select name  from major";

            //MySqlDataAdapter mda = new MySqlDataAdapter(sql, DBHelper.MySQLStr);

            //设置XXX

            //DataSet ds = new DataSet();

            //mda.Fill(ds, "MajorName");

            //DataView dv = new DataView();
            //dv = ds.Tables["student"].DefaultView;
            //MessageBox.Show(dv.ToString());

            ///
            /// 新方法
            ///

            StudentDataProvider sdp = new StudentDataProvider("select major_name  from ms_major", "MajorName");

            DataSet ds = sdp.GetRawData();

            if (ds.Tables["MajorName"].Rows.Count > 0)
            {
                foreach (DataRow row in ds.Tables[0].Rows)
                {
                    //Console.WriteLine(row[0].ToString());
                    MajorLstSource.Add(row[0].ToString());
                }
            }
            else
            {
                MessageBox.Show("数据表为空!");
            }
        }
        private DataTable Show()
        {
            DataTable dt = new DataTable();
            try
            {
                //尝试构造拼接sql语句

                //List<string> whereList = new List<string>();
                //List<SqlParameter> paramsList = new List<SqlParameter>();

                //if (MajorList.ItemsSource.ToString() != "全部")
                //{
                //    whereList.Add("major_name=@MajorName");
                //    paramsList.Add(new SqlParameter("@MajorName", MajorList.SelectedItem));
                //}
                //if (GradeList.ItemsSource.ToString() != "全部")
                //{
                //    whereList.Add("grade_name=@GradeName");
                //    paramsList.Add(new SqlParameter("@GradeName", GradeList.SelectedItem));
                //}
                //string whereSql = string.Join(" and ", whereList);

                //if (MajorList.ItemsSource.ToString() != "全部")
                //{
                //    whereList.Add("name=@MajorName");
                //    paramsList.Add(new SqlParameter("@MajorName", MajorList.Text));
                //}
                //if (GradeList.ItemsSource.ToString() != "全部")
                //{
                //    whereList.Add("name=@GradeName");
                //    paramsList.Add(new SqlParameter("@GradeName", GradeList.Text));
                //}
                //string whereSql = string.Join(" and ", whereList);
                ////StudentDataProvider sdp = new StudentDataProvider("select stu_number,stu_name,name,class_name,ban_num,dor_num from major,class,student_new,dormitory,ban where stu_dormitory=dor_id and stu_class=class_id and dor_ban=ban_id and class.major_id=major.major_id");
                ////DataSet ds = sdp.GetRawData();

                //string sql = "select stu_num,student.name,class.name,building.num,dormitory.num from school,major,class,student,dormitory,building";
                //if (whereSql.Length > 0)
                //{
                //    sql = sql  + whereSql;
                //}

                //StudentDataProvider sdp = new StudentDataProvider("select stu_number,stu_name,major_name,class_name,ban_num,dor_num from major,class,student_new,dormitory,ban where stu_dormitory=dor_id and stu_class=class_id and dor_ban=ban_id and class.major_id=major.major_id");
                //DataSet ds = sdp.GetRawData();

                //string sql = "select stu_number,stu_name,major_name,class_name,ban_num,dor_num from major,class,student_new,dormitory,ban where stu_dormitory=dor_id and stu_class=class_id and dor_ban=ban_id and class.major_id = major.major_id and ";
                //if (whereSql.Length > 0 && whereSql != null)
                //{
                //    sql = sql  + whereSql;
                //}

                string sql = "select stu_number,stu_name,major_name,class_name,ban_num,dor_num from school_major,class,student_new,dormitory,ban where stu_dormitory=dor_id and stu_class=class_id and dor_ban=ban_id and class.major_id=major.major_id";
                StudentDataProvider sdp = new StudentDataProvider(sql, "Show");

                DataSet ds = sdp.GetRawData();

                ///MySqlDataAdapter mda = new MySqlDataAdapter(sql, DBHelper.MySQLStr);
                //DataSet ds = new DataSet();

                //string sql = "select stu_number,stu_name,major_name,class_name,ban_num,dor_num from school_major,school_class,student_new,stu_dormitory,stu_building where stu_dormitory=dor_id and stu_class=class_id and dor_ban=ban_id and class.major_id=major.major_id";
                //if (whereSql.Length > 0)
                //{
                //    sql = sql  + whereSql;
                //}

                //mda.Fill(ds, "Show");

                dt = ds.Tables["Show"];
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            return dt;
        }
 public StudentsController(StudentDataProvider studentDataProvider)
 {
     _studentDataProvider = studentDataProvider;
 }