private void addStudent(string student)
{
using (var contex = new LibraryEntities())
{
Student newStudent = new Student()
{
Name = student
};
try
{
contex.Students.Add(newStudent);
contex.SaveChanges();
}
catch (DbEntityValidationException dbEx)
{
Exception raise = dbEx;
foreach (var validationErrors in dbEx.EntityValidationErrors)
{
foreach (var validationError in validationErrors.ValidationErrors)
{
string message = string.Format("{0}:{1}",
validationErrors.Entry.Entity.ToString(),
validationError.ErrorMessage);
raise = new InvalidOperationException(message, raise);
}
}
throw raise;
}
}
}
internal List <Book> GetBorrowedBooksList()
{
using (var contex = new LibraryEntities())
{
IQueryable <Book> result = (from b in contex.Books
join bb in contex.BorrowedBooks on b.Id equals bb.BookId
where bb.IsBorrowed == true
select b
);
return(result.ToList());
}
}
internal void returnBook(int bookId, string student)
{
using (var contex = new LibraryEntities())
{
var result = contex.BorrowedBooks.SingleOrDefault(bb => bb.BookId == bookId && bb.IsBorrowed == true);
if (result != null)
{
result.IsBorrowed = false;
contex.SaveChanges();
}
}
}
internal List <Book> BorrowedBookByStudent(string studentName)
{
using (var contex = new LibraryEntities())
{
IQueryable <Book> result = (from b in contex.Books
join bb in contex.BorrowedBooks on b.Id equals bb.BookId
join s in contex.Students on bb.StudentId equals s.Id
where (s.Name == studentName && bb.IsBorrowed == true)
select b
);
return(result.ToList());
}
}
internal void BorrowBook(int id, string studentName)
{
using (var contex = new LibraryEntities())
{
var studentExist = contex.Students.SingleOrDefault(s => s.Name == studentName);
if (studentExist == null)
{
addStudent(studentName);
}
registerBorrowBook(id, studentName);
}
}
private void addBorrowedBookRegister(int bookId, int studentId)
{
BorrowedBook borrowBookResgister = new BorrowedBook()
{
BookId = bookId, StudentId = studentId, IsBorrowed = true
};
using (var contex = new LibraryEntities())
{
contex.BorrowedBooks.Add(borrowBookResgister);
contex.SaveChanges();
}
}
private void registerBorrowBook(int bookId, string studentName)
{
using (var contex = new LibraryEntities())
{
var result = contex.Books.SingleOrDefault(b => b.Id == bookId);
if (result != null)
{
result.BorrowedTimes++;
contex.SaveChanges();
}
var student = contex.Students.SingleOrDefault(s => s.Name == studentName);
addBorrowedBookRegister(bookId, student.Id);
}
}
internal List <HistorialInfo> GetHistorialList()
{
using (var contex = new LibraryEntities())
{
IQueryable <HistorialInfo> result = (from b in contex.Books
join bb in contex.BorrowedBooks on b.Id equals bb.BookId
join s in contex.Students on bb.StudentId equals s.Id
select new HistorialInfo {
BookId = b.Id,
Title = b.Title,
Author = b.Author,
Genre = b.Genre,
Year = (int)b.Year,
StudentName = s.Name,
TotalTimeBorrowed = (int)b.BorrowedTimes
});
return(result.ToList());
}
}
