myoledbsmpl.cpp

Visual_C++.NET精彩案例237.rar

// MyOleDBSmpl.cpp : Defines the class behaviors for the application.
//

#include "stdafx.h"
#include "MyOleDBSmpl.h"

#include "MainFrm.h"
#include "MyOleDBSmplDoc.h"
#include "MyOleDBSmplView.h"

#include <iostream.h>
#include <fstream.h>

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

/////////////////////////////////////////////////////////////////////////////
// CMyOleDBSmplApp

BEGIN_MESSAGE_MAP(CMyOleDBSmplApp, CWinApp)
	//{{AFX_MSG_MAP(CMyOleDBSmplApp)
	ON_COMMAND(ID_APP_ABOUT, OnAppAbout)
		// 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
	// Standard file based document commands
	ON_COMMAND(ID_FILE_NEW, CWinApp::OnFileNew)
	ON_COMMAND(ID_FILE_OPEN, CWinApp::OnFileOpen)
	// Standard print setup command
	ON_COMMAND(ID_FILE_PRINT_SETUP, CWinApp::OnFilePrintSetup)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyOleDBSmplApp construction

CMyOleDBSmplApp::CMyOleDBSmplApp()
{
	// TODO: add construction code here,
	// Place all significant initialization in InitInstance
}

/////////////////////////////////////////////////////////////////////////////
// The one and only CMyOleDBSmplApp object

CMyOleDBSmplApp theApp;

/////////////////////////////////////////////////////////////////////////////
// CMyOleDBSmplApp initialization

BOOL CMyOleDBSmplApp::InitInstance()
{
	AfxEnableControlContainer();

	// Standard initialization
	// If you are not using these features and wish to reduce the size
	//  of your final executable, you should remove from the following
	//  the specific initialization routines you do not need.

#ifdef _AFXDLL
	Enable3dControls();			// Call this when using MFC in a shared DLL
#else
	Enable3dControlsStatic();	// Call this when linking to MFC statically
#endif

	// Change the registry key under which our settings are stored.
	// TODO: You should modify this string to be something appropriate
	// such as the name of your company or organization.
	SetRegistryKey(_T("Local AppWizard-Generated Applications"));

	LoadStdProfileSettings();  // Load standard INI file options (including MRU)

	// Register the application's document templates.  Document templates
	//  serve as the connection between documents, frame windows and views.

	CSingleDocTemplate* pDocTemplate;
	pDocTemplate = new CSingleDocTemplate(
		IDR_MAINFRAME,
		RUNTIME_CLASS(CMyOleDBSmplDoc),
		RUNTIME_CLASS(CMainFrame),       // main SDI frame window
		RUNTIME_CLASS(CMyOleDBSmplView));
	AddDocTemplate(pDocTemplate);

	// Parse command line for standard shell commands, DDE, file open
	CCommandLineInfo cmdInfo;
	ParseCommandLine(cmdInfo);

	// Dispatch commands specified on the command line
	if (!ProcessShellCommand(cmdInfo))
		return FALSE;

	// The one and only window has been initialized, so show and update it.
	m_pMainWnd->ShowWindow(SW_SHOW);
	m_pMainWnd->UpdateWindow();

	Doit();

	return TRUE;
}


/////////////////////////////////////////////////////////////////////////////
// CAboutDlg dialog used for App About

class CAboutDlg : public CDialog
{
public:
	CAboutDlg();

// Dialog Data
	//{{AFX_DATA(CAboutDlg)
	enum { IDD = IDD_ABOUTBOX };
	//}}AFX_DATA

	// ClassWizard generated virtual function overrides
	//{{AFX_VIRTUAL(CAboutDlg)
	protected:
	virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support
	//}}AFX_VIRTUAL

// Implementation
protected:
	//{{AFX_MSG(CAboutDlg)
		// No message handlers
	//}}AFX_MSG
	DECLARE_MESSAGE_MAP()
};

CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD)
{
	//{{AFX_DATA_INIT(CAboutDlg)
	//}}AFX_DATA_INIT
}

void CAboutDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CAboutDlg)
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CAboutDlg, CDialog)
	//{{AFX_MSG_MAP(CAboutDlg)
		// No message handlers
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

// App command to run the dialog
void CMyOleDBSmplApp::OnAppAbout()
{
	CAboutDlg aboutDlg;
	aboutDlg.DoModal();
}

/////////////////////////////////////////////////////////////////////////////
// CMyOleDBSmplApp message handlers


BOOL CMyOleDBSmplApp::ShowDataLink(_bstr_t *bstr_Connect)
{
HRESULT		hr;
	oledb::IDataSourceLocatorPtr	p_IDSL= NULL;//数据链接属性对话框对象
	_ConnectionPtr					p_conn = NULL;//存储属性对话框对象指针
	BOOL							b_ConnValid = FALSE;

	try
	{
		//创建一个数据源定位器接口（IDataSourceLocator）的实例
		hr = p_IDSL.CreateInstance( __uuidof( oledb::DataLinks ));
		TESTHR( hr );//检查错误

		//如果串给bstr_Connect的是一个空串，则创建一个新的链接
		if( *bstr_Connect == _bstr_t("") )
		{
			p_conn = p_IDSL->PromptNew();
			if( p_conn != NULL ) b_ConnValid = TRUE;		
		}
		else 
		{
			p_conn.CreateInstance( "ADODB.Connection" );
			p_conn->ConnectionString = *bstr_Connect;

			//当我们想要对链接对话框进行编辑时，需要通过IDispatch接口传递链接参数给
			//IDataSourceLocator。因此，我们需要先查询到指向IDispatch接口的指针
			IDispatch * p_Dispatch = NULL;
			p_conn.QueryInterface( IID_IDispatch, (LPVOID*) & p_Dispatch );
		
			if( p_IDSL->PromptEdit( &p_Dispatch ))
				b_ConnValid = TRUE;
		
			p_Dispatch->Release();
		}
		
		if( b_ConnValid )
			*bstr_Connect = p_conn->ConnectionString;//*/
	}
	catch( _com_error & e )
	{			
		return FALSE;
	}
	return b_ConnValid;

}

void CMyOleDBSmplApp::Doit()
{
	fstream		iosCfg;
	char		lpsz_Buffer[ 512 ];
	_bstr_t		bstr_myConnect="";

	//初始化COM
	if( FAILED(CoInitialize( NULL )) ) 
	{
		cout << "\nFailed to initialise COM";
		return;
	}

	//清空用于存储bstr_myConnect的临时缓存
	memset( lpsz_Buffer, 0, 512 );

	//打开存储连接字符串的流文件
	iosCfg.open( "my.cfg", ios::in|ios::nocreate );
	
	if( !iosCfg.fail() )
	{
		//从流文件中读出连接字符串到缓存并把它赋给bstr_myConnect		
		iosCfg.getline( lpsz_Buffer, 512 );
		bstr_myConnect = lpsz_Buffer;
	}

	//关闭流文件
	iosCfg.close();
	
	if( ShowDataLink( &bstr_myConnect ) )
	{
		//把当前属性配置信息存入到当前目录下的my.cfg文件	
		iosCfg.clear();
		iosCfg.open( "my.cfg", ios::out );
		
		if( !iosCfg.fail() )
		{
		iosCfg << (char*) bstr_myConnect << "\n";
		}
		
		iosCfg.close();
	}
	//去初始化，释放COM资源
	CoUninitialize();
}