/// <summary>
        /// Adds the list of stundent to the database.
        /// </summary>
        /// <param name="sender">The button is the sender object</param>
        /// <param name="e">The event argument for the button click event</param>
        protected void AddStudentListToDB(object sender, EventArgs e)
        {
            if (IsPostBack)
            {
                // If the user travels through the url to this page
                if (queryString == null)
                {
                    lblMessage.Text = "Invalid course.";
                }
                else
                {
                    // If no student is selected.
                    if (SelectedStudentList.SelectedValue == "")
                    {
                        lblMessage.Text = "Select any student";
                    }
                    else
                    {
                        WebSim.DTO.UserInCourse userNamecourseId = new WebSim.DTO.UserInCourse();
                        WebSim.Business.UserBusiness courseBuiCourse = new WebSim.Business.UserBusiness();

                        userNamecourseId.userName = SelectedStudentList.SelectedValue.ToString();
                        userNamecourseId.courseid = queryString;

                        courseBuiCourse.AddUserInCourse(userNamecourseId);
                    }

                }
            }
        }
        /// <summary>
        /// add user and the course to a table in the database
        /// </summary>
        /// <param name="sender">The button is the sender object</param>
        /// <param name="e">The event argument for the button click event</param>
        protected void AddUserAndCourse_Click(object sender, EventArgs e)
        {
            WebSim.DTO.UserAndCourse userInCourse = new WebSim.DTO.UserAndCourse();
            WebSim.Business.UserBusiness addUserAndCourse = new WebSim.Business.UserBusiness();

            userInCourse.userName = DropDownListUser.SelectedValue.ToString();
            userInCourse.courseName = DropDownListCourse.SelectedValue.ToString();

            addUserAndCourse.AddUserToCourse(userInCourse);
        }
        /// <summary>
        /// Sets the student list for the subject
        /// </summary>
        private void ListView_Student()
        {
            WebSim.Business.UserBusiness userBuiCourse = new WebSim.Business.UserBusiness();

            WebSim.DTO.CourseID courseid = new WebSim.DTO.CourseID();
            courseid.courseid = queryString;
            IList<WebSim.DTO.StudentDetail> studDetail = userBuiCourse.GetStudentList(courseid);

            // adding student name to the list
            foreach (var item in studDetail)
            {

                StudentList.Items.Add(new ListItem(item.userName,item.studentId.ToString()));

            }
        }