private void Button1_Click(object sender, EventArgs e)
{
books_reserved br = new books_reserved();
br.book_id = CB_Book.SelectedValue.ToString();
br.student_id = CB_Reader.SelectedValue.ToString();
br.reserv_ends = DateTime.Today.AddDays(3);
db.books_reserved.Add(br);
db.SaveChanges();
}
private void button1_Click(object sender, EventArgs e)
{
if (bookId == -1 || studID == "")
{
MessageBox.Show("Необходимо выбрать книгу и студента перед выдачей", "Ошибка", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
else
{
if (MessageBox.Show(string.Format("Студенту {0} {1} {2} группы {3} выдается книга {4} {5}. Информация верна?",
tb_studFirstName.Text, tb_studMiddleName.Text, tb_studLastName.Text, tb_studGroup.Text, tb_bookAuthor.Text, tbBookTitle.Text
), "Необходимо подтверждение", MessageBoxButtons.YesNo, MessageBoxIcon.Question) == DialogResult.Yes)
{
OleDbConnection conn = new OleDbConnection(Properties.Settings.Default.MainConnectionString);
OleDbCommand com = new OleDbCommand("", conn);
conn.Open();
com.CommandText = "select amount from books_available where book_id = " + bookId;
int bookQty = int.Parse(com.ExecuteScalar().ToString());
if (bookQty == 0)
{
MessageBox.Show("Нет доступных книг для выдачи");
}
else
{
com.CommandText = "insert into books_taken(book_id, student_id,return_date) " +
"values(" + bookId + ", '" + studID + "', '" + dt_returnDate.Value.ToString("yyyMMdd") + "')";
int res1 = com.ExecuteNonQuery();
com.CommandText = "update books_available set amount=amount-1 where book_id = " + bookId;
int res2 = com.ExecuteNonQuery();
if (res1 > 0 && res2 > 0)
{
MessageBox.Show("Книга выдана успешно");
}
List <books_reserved> all_reserves = db.books_reserved.ToList();
books_reserved cur_reserve = all_reserves.Where(rr => rr.book_id == book_isbn && rr.student_id == studID).FirstOrDefault();
if (cur_reserve != null)
{
if (MessageBox.Show("Студент резервировал эту книгу. Закрыть его резерв?", "", MessageBoxButtons.YesNo) == DialogResult.Yes)
{
cur_reserve.taken = true;
db.SaveChanges();
}
}
}
conn.Close();
}
}
}