daoqrydoc.cpp

Visual C++ 实践与提高--数据库篇的源代码。很好的东西。欢迎下载。

// DAOQryDoc.cpp : implementation of the CDAOQryDoc class
//

#include "stdafx.h"
#include "DAOQry.h"
#include "DaoListView.h"
#include "DaoTreeView.h"
#include "DAOQryDoc.h"

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

/////////////////////////////////////////////////////////////////////////////
// CDAOQryDoc

IMPLEMENT_DYNCREATE(CDAOQryDoc, CDocument)

BEGIN_MESSAGE_MAP(CDAOQryDoc, CDocument)
	//{{AFX_MSG_MAP(CDAOQryDoc)
		// NOTE - the ClassWizard will add and remove mapping macros here.
		//    DO NOT EDIT what you see in these blocks of generated code!
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CDAOQryDoc construction/destruction

CDAOQryDoc::CDAOQryDoc()
{
	//初始化指针
	m_pDB = NULL;
	m_pTreeView = NULL;
	m_pListView = NULL;
}

CDAOQryDoc::~CDAOQryDoc()
{
}

BOOL CDAOQryDoc::OnNewDocument()
{
	if (!CDocument::OnNewDocument())
		return FALSE;

	// TODO: add reinitialization code here
	// (SDI documents will reuse this document)

	return TRUE;
}



/////////////////////////////////////////////////////////////////////////////
// CDAOQryDoc serialization

void CDAOQryDoc::Serialize(CArchive& ar)
{
	if (ar.IsStoring())
	{
		// TODO: add storing code here
	}
	else
	{
		// TODO: add loading code here
	}
}

/////////////////////////////////////////////////////////////////////////////
// CDAOQryDoc diagnostics

#ifdef _DEBUG
void CDAOQryDoc::AssertValid() const
{
	CDocument::AssertValid();
}

void CDAOQryDoc::Dump(CDumpContext& dc) const
{
	CDocument::Dump(dc);
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CDAOQryDoc commands

BOOL CDAOQryDoc::OnOpenDocument(LPCTSTR lpszPathName) 
{
	if (!CDocument::OnOpenDocument(lpszPathName))
		return FALSE;
	
	CDaoDatabase* tmpDB = new CDaoDatabase;

	//在给m_pDB赋值之前，先试着打开数据库；
	//若成功，则给其赋值
	try
	{
		tmpDB->Open(lpszPathName);
	}
	catch (CDaoException* e)
	{
		DisplayDaoException(e);
		delete tmpDB;
		e->Delete();
		return FALSE;
	}

	//删除指向上次所打开数据库的指针
	if (m_pDB)
	{
		if (m_pDB->IsOpen())
			m_pDB->Close();
		delete m_pDB;
	}

	//给指针赋新值
	m_pDB = tmpDB;
	m_pTreeView->m_pDB = m_pDB;
	m_pListView->m_pDB = m_pDB;

	//刷新视图
	RefreshViews();	
	return TRUE;
}

void CDAOQryDoc::RefreshViews()
{
	if (m_pDB)
	{
		//刷新列表视图
		if (m_pListView)
			m_pListView->EraseList();

		//刷新树视图
		if (m_pTreeView)
			m_pTreeView->PopulateTree();
	}
}