protected void btnLate_Click(object sender, EventArgs e)
    {
        var schoolId   = info.getId();
        var semesterId = MyDate.getCurrentSemesterId();
        //     var LibrarianId = info.getSchoolLibrarian();

        var preInfo = (from k in km.BorrowsofStudents
                       join emp in km.Students on k.StudentId equals emp.IdentityNumber
                       where k.SchoolId == schoolId && k.SemesterId == semesterId &&
                       k.isReturn == false && k.DateReturn < DateTime.Now
                       orderby k.DateReturn, k.DateBorrow
                       select new
        {
            emp.Name,
            k.DateReturn,
            k.DateBorrow,
            k.BookId,
            auther = (from b in km.Books where b.Id == k.BookId select b.Auther).FirstOrDefault(),
            bookname = (from b in km.Books where b.Id == k.BookId select b.Title).FirstOrDefault(),
            k.isReturn
        }).ToList();

        LstStudentsBorrow.DataSource = preInfo;
        LstStudentsBorrow.DataBind();
    }
    public void FillBorrowNotReturn()
    {
        var schoolId   = info.getId();
        var semesterId = MyDate.getCurrentSemesterId();


        if (Request.QueryString["BookId"] != null)
        {
            int Bookid  = int.Parse(Request.QueryString["BookId"]);
            var preInfo = (from k in km.BorrowsofEmployees
                           join emp in km.Employees on k.EmployeeId equals emp.IdentityNumber
                           where  k.SchoolId == schoolId && k.SemesterId == semesterId && k.isReturn == false &&
                           k.BookId == Bookid
                           orderby k.DateReturn, k.DateBorrow
                           select new
            {
                k.Id,
                emp.Name,
                k.DateReturn,
                k.DateBorrow,
                k.BookId,
                auther = (from b in km.Books where b.Id == k.BookId select b.Auther).FirstOrDefault(),
                bookname = (from b in km.Books where b.Id == k.BookId select b.Title).FirstOrDefault(),
                k.isReturn
            }).ToList();

            LstEmployeeBorrow.DataSource = preInfo;
            LstEmployeeBorrow.DataBind();


            var preInfo2 = (from k in km.BorrowsofStudents
                            join emp in km.Students on k.StudentId equals emp.IdentityNumber
                            where k.SchoolId == schoolId && k.SemesterId == semesterId && k.isReturn == false &&
                            k.BookId == Bookid
                            orderby k.DateReturn, k.DateBorrow
                            select new
            {
                k.Id,
                emp.Name,
                k.DateReturn,
                k.DateBorrow,
                k.BookId,
                auther = (from b in km.Books where b.Id == k.BookId select b.Auther).FirstOrDefault(),
                bookname = (from b in km.Books where b.Id == k.BookId select b.Title).FirstOrDefault(),
                k.isReturn
            }).ToList();

            LstStudentsBorrow.DataSource = preInfo2;
            LstStudentsBorrow.DataBind();
        }
    }
    public void FillBorrowAll()
    {
        var schoolId   = info.getId();
        var semesterId = MyDate.getCurrentSemesterId();
        //     var LibrarianId = info.getSchoolLibrarian();

        var preInfo = (from k in km.BorrowsofStudents
                       join e in km.Students on k.StudentId equals e.IdentityNumber
                       where k.SchoolId == schoolId && k.SemesterId == semesterId
                       orderby k.DateReturn, k.DateBorrow
                       select new
        {
            e.Name,
            k.DateReturn,
            k.DateBorrow,
            k.BookId,
            auther = (from b in km.Books where b.Id == k.BookId select b.Auther).FirstOrDefault(),
            bookname = (from b in km.Books where b.Id == k.BookId select b.Title).FirstOrDefault(),
            k.isReturn
        }).ToList();

        LstStudentsBorrow.DataSource = preInfo;
        LstStudentsBorrow.DataBind();
    }