protected void BTNADDED_Click1(object sender, EventArgs e)
        {
            int       num = 0;
            string    sql = "select * from [DepartmentCourses] where Department='" + Session["Department"] + "' and Year='" + Session["Year"] + "' and Semster='" + Session["Semester"] + "'";
            DataTable dt  = DBFunctions.SelectFromTable(sql);

            GridViewRegistering.DataSource = (dt);
            //  DataTable dt1=null;

            if (((CheckBox)GridViewRegistering.Rows[0].FindControl("CheckBox1")).Checked == true)
            {
                string s = dt.Rows[0]["IdCourse"].ToString();

                string          sql2         = "select * from [DepartmentCourses] where IdCourse= '" + s + "'";
                DataTable       dt2          = DBFunctions.SelectFromTable(sql2);
                string          muchStudents = dt.Rows[0]["RegisteredStudents"].ToString();
                string          maxStudent   = dt.Rows[0]["MaxStudent"].ToString();
                StudentAtCourse c            = new StudentAtCourse(s, Session["ID"].ToString());
                if (Convert.ToInt32(muchStudents) < Convert.ToInt32(maxStudent))
                {
                    if (c.insertCourseForStudent())
                    {
                        num = Convert.ToInt32(muchStudents) + 1;
                        DepartmentCourses d = new DepartmentCourses(num.ToString(), maxStudent, s);
                        d.UpdateRegisteringStudent();
                        lblMsn.Visible = true;
                        lblMsn.Text    = "Has Been Added";
                    }
                    else
                    {
                        lblMsn.Visible = true; lblMsn.Text = "Already Exsist!";
                    }
                    dt1 = DBFunctions.SelectFromTable(sql2);
                }
            }
            for (int i = 1; i < dt.Rows.Count; i++)
            {
                if (((CheckBox)GridViewRegistering.Rows[i].FindControl("CheckBox1")).Checked == true)
                {
                    string s = dt.Rows[i]["IdCourse"].ToString();

                    string          muchStudents = dt.Rows[i]["RegisteredStudents"].ToString();
                    string          maxStudent   = dt.Rows[i]["MaxStudent"].ToString();
                    StudentAtCourse c            = new StudentAtCourse(s, Session["ID"].ToString());


                    if (Convert.ToInt32(muchStudents) < Convert.ToInt32(maxStudent))
                    {
                        if (c.insertCourseForStudent())
                        {
                            num = Convert.ToInt32(muchStudents) + 1;
                            DepartmentCourses d = new DepartmentCourses(num.ToString(), maxStudent, s);
                            d.UpdateRegisteringStudent();
                            lblMsn.Visible = true;
                            lblMsn.Text    = "Has Been Added";
                        }

                        else
                        {
                            lblMsn.Visible = true; lblMsn.Text = "Already Exsist!";
                        }
                    }

                    else
                    {
                        lblMsn.Visible = true; lblMsn.Text = "There is no place in this course!";
                    }
                    string    sql2 = "select * from [DepartmentCourses] where IdCourse= '" + s + "'";
                    DataTable dt2  = DBFunctions.SelectFromTable(sql2);
                    if (dt1 == null)
                    {
                        dt1 = dt2;
                    }
                    else
                    {
                        dt1.Merge(dt2);
                    }
                }
            }
            GridViewAdded.DataSource = (dt1);
            newDt = DBFunctions.CopyDataTable(dt1, dt1.Rows.Count);
            DataBind();
        }