bookborrowdlg.cpp

设计并实现一个精简的图书管理系统, 要求具有图书入库、查询、借书、还书、 借书证管理等功能。

// BookBorrowDlg.cpp : implementation file
//

#include "stdafx.h"
#include "library.h"
#include "BookBorrowDlg.h"
#include "BookRS.h"
#include "BorrowRS.h"
#include "CardRS.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CBookBorrowDlg dialog


CBookBorrowDlg::CBookBorrowDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CBookBorrowDlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CBookBorrowDlg)
	m_strBookNum = _T("");
	m_strCardNum = _T("");
	//}}AFX_DATA_INIT
}


void CBookBorrowDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CBookBorrowDlg)
	DDX_Text(pDX, IDC_BOOK_NUM, m_strBookNum);
	DDX_Text(pDX, IDC_CARD_NUM, m_strCardNum);
	//}}AFX_DATA_MAP
}


BEGIN_MESSAGE_MAP(CBookBorrowDlg, CDialog)
	//{{AFX_MSG_MAP(CBookBorrowDlg)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CBookBorrowDlg message handlers

void CBookBorrowDlg::OnOK() 
{
	// TODO: Add extra validation here
	UpdateData();
	if(!IsValidCard(m_strCardNum)){
		CDialog::OnOK();
		return;
	}
	if(AnyBookExpired(m_strCardNum)){
		CDialog::OnOK();
		return;
	}
	if(!AllowedToBorrow(m_strBookNum)){
		CDialog::OnOK();
		return;
	}
	if(BorrowBook(m_strCardNum,m_strBookNum)){
		AfxMessageBox("借书成功");
	}
	else{
		AfxMessageBox("借书失败");
	}
	CDialog::OnOK();
}

bool CBookBorrowDlg::IsValidCard(const CString &cardNum)
{
	if(!m_cardSet.IsOpen()){
		m_cardSet.Open();
	}
	m_cardSet.m_strFilter.Format("Cno= %s",cardNum);
	m_cardSet.Requery();

	if(m_cardSet.IsEOF()){
		AfxMessageBox("该卡号不存在");
		return false;
	}
	return true;
}

bool CBookBorrowDlg::AnyBookExpired(const CString &cardNum)
{

	int nBooks=0;
	if(!m_borrowSet.IsOpen()){
		m_borrowSet.Open();
	}
	m_borrowSet.m_strFilter.Format("Cno=%s and Return_date is null",cardNum);
	m_borrowSet.Requery();
	CTime today = CTime::GetCurrentTime();
	CTimeSpan diffDays;
	while(!m_borrowSet.IsEOF())
	{
		nBooks++;
		diffDays=today - m_borrowSet.m_borrow_date;
		if(diffDays.GetDays()>30)
		{
			AfxMessageBox("您有书过期了");
			return true;
		}
		m_borrowSet.MoveNext();
	}
	if(nBooks>12)
	{
		AfxMessageBox("您借书总数超额了");
			return true;
	}
	return false;
}

bool CBookBorrowDlg::AllowedToBorrow(const CString &bno)
{

	if(!m_bookSet.IsOpen())
	{
		m_bookSet.Open();
	}
	m_bookSet.m_strFilter.Format("bno= %s",bno);
	m_bookSet.Requery();
	if(m_bookSet.IsEOF())
	{
		AfxMessageBox("该书不存在");
		return false;
	}
	if(m_bookSet.m_stocked==0)
	{
		AfxMessageBox("本书已经借光了");
		return false;
	}
	return true;
}

bool CBookBorrowDlg::BorrowBook(const CString &cardNum,const CString &bookNum)
{
	CTimeSpan span(30,0,0,0);
	CTime nextMonth=CTime::GetCurrentTime()+span;

	if(! m_bookSet.IsOpen())
	{
		m_bookSet.Open();
	}
	m_bookSet.m_strFilter.Format("bno =% s",bookNum);
	m_bookSet.Requery();
	m_bookSet.Edit();
    m_bookSet.m_stocked=m_bookSet.m_stocked-1;
	m_bookSet.Update();
	if(!m_borrowSet.IsOpen())
	{
		m_borrowSet.Open();
	}
	m_borrowSet.AddNew();
	m_borrowSet.m_bno=bookNum;
	m_borrowSet.m_cno=cardNum;
	m_borrowSet.m_borrow_date=CTime::GetCurrentTime();
	m_borrowSet.m_return_date=nextMonth;
//	m_borrowSet.m_id=Adid;   //需要增加管理员的id,设其id为全局变量  Adid
    m_borrowSet.Update();
	m_borrowSet.Requery();
	return true;

}