寫student類中的select，delete，update，insert方法並在objectDataSource中應用（分別寫兩個，一個返回datatable，一個使用list）

public DataTable StudentsSelect()
        {
            string sql = "select sid,sname,sex,age,photo from student";
            return sqlHealpler.sqlHealper.ExecuteTable(sql);
        }
        public int StudentDelete(int sid)
        {
            string sql = "delete from student where sid=@id";
            SqlParameter pms=new SqlParameter("@id",sid);
            return sqlHealpler.sqlHealper.ExecturNonQuery(sql,pms);
        }

        public int StudentInsert(int sid, string sname, string sex, int age, string photo)
        {
            string sql = "insert into student values(@sname,@sex,@age,@photo)";
            SqlParameter[] pms = new SqlParameter[]
            {
            new SqlParameter("@sname",sname),
            new SqlParameter("@sex",sex),
            new SqlParameter("@age",age),
            new SqlParameter("@photo",photo),
            //new SqlParameter("@id",sid)
            };
            return sqlHealpler.sqlHealper.ExecturNonQuery(sql, pms);
        }

        public int StudentUpdate(int sid,string sname,string sex,int age,string photo)
        {
            string sql = "Update student set sname=@sname,sex=@sex,age=@age,photo=@photo where sid=@id";
            SqlParameter[] pms = new SqlParameter[]
            {
            new SqlParameter("@sname",sname),
            new SqlParameter("@sex",sex),
            new SqlParameter("@age",age),
            new SqlParameter("@photo",photo),
            new SqlParameter("@id",sid)
            };
            return sqlHealpler.sqlHealper.ExecturNonQuery(sql, pms);
        }

返回list

        public int sid { get; set; }
        public string sname { get; set; }
        public string sex { get; set; }
        public int age { get; set; }
        public string photo { get; set; }

       public List<Student> GetStudents()
        {
            string sql = "select sid,sname,sex,age,photo from student";
            DataTable dt = sqlHealpler.sqlHealper.ExecuteTable(sql);
            List<Student> list = new List<Student>();
            foreach (DataRow row in dt.Rows)
            {
                Student stu = new Student();
                stu.sid = (int)row[0];
                stu.sname = row[1].ToString();
                stu.sex = row[2].ToString();
                stu.age = Convert.ToInt32(row[3]);
                stu.photo = row[4].ToString();
                list.Add(stu);
            }
            return list;
        }