public void Add(Book newBook) { var book = Get(newBook.Id); if (book == null) { _context.Add(newBook); _context.SaveChanges(); } }
public void Add(Student student) { var newStudent = Get(student.Id); if (newStudent == null) { _context.Add(student); _context.SaveChanges(); } }
public string AssignBook(int bookId, int studentId) { var isValid = ValidateBookAndStudent(bookId, studentId); if (!isValid) { return("Either student or book does not exist!"); } var isBookAlreadyIssued = _context.BookAssignToStudents.Any(a => a.Book.Id == bookId && a.Book.IsIssued == true); if (isBookAlreadyIssued) { return("Book is already issued to the student."); } var book = _context.Books.First(a => a.Id == bookId); book.IsIssued = true; _context.Update(book); var now = DateTime.Now; var student = _context.Students.FirstOrDefault(a => a.Id == studentId); var bookAssignToStudent = new BookAssignToStudent { BookId = bookId, Book = book, StudentId = studentId, Student = student, IssueDate = now, DueDate = now.AddDays(7) }; _context.Add(bookAssignToStudent); _context.SaveChanges(); return("Success"); }