void fillCourseList()
    {
        DataTable dtTtr = new DataTable();

        dtTtr = ClsCource.GetCourse();
        lstCourses.DataSource     = dtTtr;
        lstCourses.DataTextField  = "CourseName";
        lstCourses.DataValueField = "CourseID";
        lstCourses.DataBind();
    }
    public static string getCourseList()
    {
        DataTable dt = ClsCource.GetCourse();

        if (dt != null && dt.Rows.Count > 0)
        {
            return(JsonConvert.SerializeObject(dt));
        }
        else
        {
            return("empty");
        }
    }