void LoadData()
        {
            //student load and display
            Student_Model s1 = new Student_Model();

            s1.GetAll();

            grdStudent.DataSource = s1.Table;
            grdStudent.Refresh();

            //Parent load and display
            Parent_Model p1 = new Parent_Model();

            p1.GetAll();

            grdParent.DataSource = p1.Table;
            grdParent.Refresh();
            //Menu load and display
            Menu_Model m1 = new Menu_Model();

            m1.GetAll();

            grdMenu.DataSource = m1.Table;
            grdMenu.Refresh();
        }
        private void button2_Click(object sender, EventArgs e)
        {
            if (!string.IsNullOrWhiteSpace(textBox1.Text))
            {
                Student_Model s1 = new Student_Model();
                s1.Name = textBox1.Text;
                s1.Create();

                textBox1.Text = "";
                LoadData();
            }
        }
        private void btn_delete_Click(object sender, EventArgs e)
        {
            if (!string.IsNullOrWhiteSpace(lblStudentId.Text))
            {
                Student_Model s1 = new Student_Model();
                s1.Id = Convert.ToInt32(lblStudentId.Text);

                s1.Delete();

                textBox1.Text     = "";
                lblStudentId.Text = "";
                LoadData();
            }
        }
    public List<Student_Model> GetDSHV_trongTrungTam(string BranchID)
    {
        List<Student_Model> rs = new List<Student_Model>();
        ThuVien tv = new ThuVien();

        DataTable tbStudent = tv.SP_SelectDataTable("USP_Student_GetBySomeConditional", new string[] { "@flag", "@BranchID" }, new object[] { 12, BranchID });
            if (tbStudent.Rows.Count > 0)
            {
                for (int i = 0; i < tbStudent.Rows.Count; i++)
                {
                    Student_Model stmodel = new Student_Model();
                    stmodel.StudentID = tbStudent.Rows[i]["StudentID"].ToString();
                    stmodel.StudentName = tbStudent.Rows[i]["StudentName"].ToString();
                    rs.Add(stmodel);
                }
            }

        return rs;
    }