public ObservableCollection <Entity.Student> GetStudentsData()
        {
            ObservableCollection <Entity.Student> studentsList = new ObservableCollection <Entity.Student>();

            using (demoEntities db = new demoEntities())
            {
                var students = db.GetStudents();
                foreach (var student in students)
                {
                    Student stud = new Student()
                    {
                        Id         = student.Id,
                        Name       = student.Name,
                        Mobile     = student.Mobile,
                        Address    = student.Address,
                        Stream     = student.Stream,
                        StreamName = student.StreamName
                    };
                    studentsList.Add(stud);
                }
            }
            return(studentsList);
        }