public bool insertLending(Lending lending) { try { conn.Open(); OleDbCommand cmd = new OleDbCommand(insertBorrowSQL, conn); cmd.Parameters.AddWithValue("@isbn", lending.ISBN); cmd.Parameters.AddWithValue("@borrowtime", GetDateWithoutMilliseconds(DateTime.Now)); cmd.Parameters.AddWithValue("@borrowerid", lending.BorrowerID); cmd.Parameters.AddWithValue("@borrowername", lending.BorrowerName); cmd.ExecuteNonQuery(); return(true); } catch (OleDbException ex) { Console.WriteLine(ex); } finally { conn.Close(); } return(false); }
public int returnBook(Lending lending) { try { conn.Open(); OleDbCommand cmd = new OleDbCommand(returnBookSQL, conn); cmd.Parameters.AddWithValue("@returntime", GetDateWithoutMilliseconds(DateTime.Now)); cmd.Parameters.AddWithValue("@isbn", lending.ISBN); cmd.Parameters.AddWithValue("@borrowername", lending.BorrowerName); cmd.Parameters.AddWithValue("@borrowerid", lending.BorrowerID); int rowsAffected = cmd.ExecuteNonQuery(); return(rowsAffected); } catch (OleDbException ex) { Console.WriteLine(ex); } finally { conn.Close(); } return(0); }
public bool checkStudentBookUnreturnExist(Lending lending) { try { conn.Open(); OleDbCommand cmd = new OleDbCommand(selectStudentBookUnreturnedCountSQL, conn); cmd.Parameters.AddWithValue("@isbn", lending.ISBN); cmd.Parameters.AddWithValue("@borrowername", lending.BorrowerName); cmd.Parameters.AddWithValue("@borrowerid", lending.BorrowerID); OleDbDataReader reader = cmd.ExecuteReader(); if (reader.HasRows || reader != null) { while (reader.Read()) { return(true); } } else { return(false); } } catch (OleDbException ex) { Console.WriteLine(ex); } finally { conn.Close(); } return(false); }
private void continue_btn_Click(object sender, EventArgs e) { ArrayList lendingList = new ArrayList(); string[] allTextBoxes = { book1ISBN_textbox.Text, book2ISBN_textbox.Text, book3ISBN_textbox.Text, book4ISBN_textbox.Text }; // book id list for duplicate checking only List <string> isbnListForDC = new List <string>(); int emptyTextboxCount = 0; foreach (string ISBN in allTextBoxes) { if (!String.IsNullOrEmpty(ISBN)) { Lending lending = new Lending(); lending.ISBN = ISBN.ToUpper(); lendingList.Add(lending); isbnListForDC.Add(ISBN.ToUpper()); } else { emptyTextboxCount++; } } if (emptyTextboxCount == allTextBoxes.Count()) { MessageBox.Show("Please scan a book's barcode.", "Empty Field", MessageBoxButtons.OK, MessageBoxIcon.Error); return; } if (!checkDuplicateBook(isbnListForDC)) { if (actionType.Equals("Borrow")) { MessageBox.Show("You cannot borrow the same book.", "Duplicate Book", MessageBoxButtons.OK, MessageBoxIcon.Error); return; } else if (actionType.Equals("Return")) { MessageBox.Show("You are trying to return many same books.", "Duplicate Book", MessageBoxButtons.OK, MessageBoxIcon.Error); return; } } // check if book id is valid foreach (Lending lending in lendingList) { if (dbManager.isbnExists(lending.ISBN) == false) { MessageBox.Show("The book ID " + lending.ISBN + " does not exist, no such book.", "Invalid Book ID", MessageBoxButtons.OK, MessageBoxIcon.Error); return; } } if (actionType.Equals("Borrow")) { foreach (Lending lending in lendingList) { int unreturnedQuantity = dbManager.selectUnreturnQuantity(lending.ISBN); int totalQuantity = dbManager.selectBook(lending.ISBN).Quantity; bool bookAvailable = totalQuantity > unreturnedQuantity; if (bookAvailable == false) { MessageBox.Show("Please return the book ID " + lending.ISBN + " before trying to borrow.", "Book Not Available", MessageBoxButtons.OK, MessageBoxIcon.Error); return; } } Action frmAction = new Action(actionType, lendingList); frmAction.Show(); this.Owner = frmAction; this.Hide(); } else if (actionType.Equals("Return")) //return book { Action frmAction = new Action(actionType, lendingList); frmAction.Show(); this.Owner = frmAction; this.Hide(); } }