ex070202dlg.cpp

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// Ex070202Dlg.cpp : implementation file
//

#include "stdafx.h"
#include "Ex070202.h"
#include "Ex070202Dlg.h"

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

/////////////////////////////////////////////////////////////////////////////
// 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)
	//}}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()

/////////////////////////////////////////////////////////////////////////////
// CEx070202Dlg dialog

CEx070202Dlg::CEx070202Dlg(CWnd* pParent /*=NULL*/)
	: CDialog(CEx070202Dlg::IDD, pParent)
{
	//{{AFX_DATA_INIT(CEx070202Dlg)
	m_strFileName = _T("d:\\test.txt");
	m_uScore = 80;
	//}}AFX_DATA_INIT
	// Note that LoadIcon does not require a subsequent DestroyIcon in Win32
	m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME);
}

void CEx070202Dlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CEx070202Dlg)
	DDX_Text(pDX, IDC_PATHFILENAME, m_strFileName);
	DDX_Text(pDX, IDC_SCORE_EDIT, m_uScore);
	DDV_MinMaxUInt(pDX, m_uScore, 0, 100);
	//}}AFX_DATA_MAP
}

BEGIN_MESSAGE_MAP(CEx070202Dlg, CDialog)
	//{{AFX_MSG_MAP(CEx070202Dlg)
	ON_WM_SYSCOMMAND()
	ON_WM_PAINT()
	ON_WM_QUERYDRAGICON()
	ON_BN_CLICKED(IDC_SCORE, OnScore)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CEx070202Dlg message handlers

BOOL CEx070202Dlg::OnInitDialog()
{
	CDialog::OnInitDialog();

	// Add "About..." menu item to system menu.

	// IDM_ABOUTBOX must be in the system command range.
	ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX);
	ASSERT(IDM_ABOUTBOX < 0xF000);

	CMenu* pSysMenu = GetSystemMenu(FALSE);
	if (pSysMenu != NULL)
	{
		CString strAboutMenu;
		strAboutMenu.LoadString(IDS_ABOUTBOX);
		if (!strAboutMenu.IsEmpty())
		{
			pSysMenu->AppendMenu(MF_SEPARATOR);
			pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu);
		}
	}

	// Set the icon for this dialog.  The framework does this automatically
	//  when the application's main window is not a dialog
	SetIcon(m_hIcon, TRUE);			// Set big icon
	SetIcon(m_hIcon, FALSE);		// Set small icon
	
	// TODO: Add extra initialization here
	
	return TRUE;  // return TRUE  unless you set the focus to a control
}

void CEx070202Dlg::OnSysCommand(UINT nID, LPARAM lParam)
{
	if ((nID & 0xFFF0) == IDM_ABOUTBOX)
	{
		CAboutDlg dlgAbout;
		dlgAbout.DoModal();
	}
	else
	{
		CDialog::OnSysCommand(nID, lParam);
	}
}

// If you add a minimize button to your dialog, you will need the code below
//  to draw the icon.  For MFC applications using the document/view model,
//  this is automatically done for you by the framework.

void CEx070202Dlg::OnPaint() 
{
	if (IsIconic())
	{
		CPaintDC dc(this); // device context for painting

		SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

		// Center icon in client rectangle
		int cxIcon = GetSystemMetrics(SM_CXICON);
		int cyIcon = GetSystemMetrics(SM_CYICON);
		CRect rect;
		GetClientRect(&rect);
		int x = (rect.Width() - cxIcon + 1) / 2;
		int y = (rect.Height() - cyIcon + 1) / 2;

		// Draw the icon
		dc.DrawIcon(x, y, m_hIcon);
	}
	else
	{
		CDialog::OnPaint();
	}
}

// The system calls this to obtain the cursor to display while the user drags
//  the minimized window.
HCURSOR CEx070202Dlg::OnQueryDragIcon()
{
	return (HCURSOR) m_hIcon;
}

const int nFileHeadLeng = 256 ;//文件头的长度
char * szFileHeadFlag = "Ex070202---Flag" ;//文件标志,避免误操作

//生成备份文件
CString CreateBakFile(PBYTE pbFile,DWORD nLeng,UINT uScore)
{
	HANDLE hBakFile = INVALID_HANDLE_VALUE ;
	HANDLE hBakFileMapping = NULL ;
	PBYTE  pbBakFile = NULL ;
	bool   bSuc = false ;

	//生成备份文件的名称
	char szTmpPath[MAX_PATH+1] ;
	char szBakFileName[MAX_PATH+1] ;
	::GetTempPath(MAX_PATH,szTmpPath);
	::GetTempFileName(szTmpPath,"Score",0,szBakFileName);
	
	hBakFile = CreateFile(szBakFileName, 
		GENERIC_READ | GENERIC_WRITE, 
		FILE_SHARE_READ, 
		NULL, 
		CREATE_ALWAYS, 
		FILE_ATTRIBUTE_NORMAL, 
		NULL); 	
	if( INVALID_HANDLE_VALUE == hBakFile )
	{
		bSuc = false ;
		goto End ;
	}
	hBakFileMapping = CreateFileMapping(hBakFile,NULL,PAGE_READWRITE, 
		0, nLeng+ nFileHeadLeng , NULL); 
	if( NULL == hBakFileMapping )
	{
		bSuc = false ;
		goto End ;
	}
	pbBakFile = (PBYTE)MapViewOfFile(hBakFileMapping, FILE_MAP_ALL_ACCESS, 0,0, nLeng+nFileHeadLeng);
	if( NULL == pbBakFile )
	{
		bSuc = false ;
		goto End ;
	}
	
	//原制原有内容
	memcpy(pbBakFile+nFileHeadLeng,pbFile,nLeng);
	{//写文件头
		char szTmp[nFileHeadLeng] = {0} ;
		memcpy(szTmp,szFileHeadFlag,strlen(szFileHeadFlag)+1);
		sprintf(szTmp+strlen(szFileHeadFlag)+1,"%3d",uScore);
		memcpy(pbBakFile,szTmp,nFileHeadLeng);
	}

End :
	if( NULL != pbBakFile )
		UnmapViewOfFile(pbBakFile);
	if( NULL != hBakFileMapping )
		CloseHandle(hBakFileMapping);
	if( INVALID_HANDLE_VALUE != hBakFile)
		CloseHandle(hBakFile); 
	
	return szBakFileName ;
}



bool CEx070202Dlg::Score()
{
	HANDLE hFile =  INVALID_HANDLE_VALUE ;
	HANDLE hFileMapping = NULL ;
	PBYTE pbFile = NULL ;
	bool bSuc = true ;
	DWORD nLeng ;
	CString strBakFileName ;

	// 创建文件内核对象，其句柄保存于hFile 
	hFile = CreateFile(m_strFileName, 
		GENERIC_READ, 
		FILE_SHARE_READ, 
		NULL, 
		OPEN_ALWAYS, 
		FILE_ATTRIBUTE_NORMAL, 
		NULL); 	
	if( INVALID_HANDLE_VALUE == hFile)
	{
		bSuc = false ;
		goto End ;
	}
	//取得文件长度
	nLeng = ::SetFilePointer(hFile,0,0,FILE_END);
	{//检查是否已经有文件头
		BYTE bData[16] = {0};
		DWORD dLeng ;
		::SetFilePointer(hFile,0,0,FILE_BEGIN);
		::ReadFile(hFile,bData,16,&dLeng,NULL);
		if( 0 == memcmp(bData,szFileHeadFlag,16))
		{//取得分数
			char szScore[4] = {0} ;
			::ReadFile(hFile,szScore,4,&dLeng,NULL);
			GetDlgItem(IDC_FILECONTENT)->SetWindowText("此文件已经打过分了!\n分数是"+ CString(szScore));
			goto End ;
		}
	}
	// 创建文件映射内核对象，句柄保存于hFileMapping 
	hFileMapping = CreateFileMapping(hFile,NULL,PAGE_READONLY, 
		0, 0, NULL); 
	if( NULL == hFileMapping )
	{
		bSuc = false ;
		goto End ;
	}
	// 将文件数据映射到进程的地址空间 
	pbFile = (PBYTE)MapViewOfFile(hFileMapping, FILE_MAP_READ, 0,	0, nLeng); 
	if(NULL == pbFile)
	{
		bSuc = false ;
		goto End ;
	}
	{//将内容显示在编辑框上.当内容比较多时,这显示一部分.
		int nShowLeng = ( nLeng < 10000 ) ? nLeng : 10000 ;
		char * pszShowText = new char[nShowLeng+1] ;
		memcpy(pszShowText,pbFile,nShowLeng);
		pszShowText[nShowLeng] = '\0' ;
		GetDlgItem(IDC_FILECONTENT)->SetWindowText(pszShowText);
		delete [] pszShowText ;
	}
	strBakFileName = CreateBakFile(pbFile,nLeng,m_uScore) ;
	if(strBakFileName.IsEmpty())
	{
		bSuc = false ;
		goto End ;
	}	 
		
End:// 释放资源 
	if( NULL != pbFile)
		UnmapViewOfFile(pbFile);
	if( NULL != hFileMapping)
		CloseHandle(hFileMapping);
	if( INVALID_HANDLE_VALUE != hFile )
		CloseHandle(hFile);
	if(!strBakFileName.IsEmpty())//用备份文件替换原有文件
		bSuc = CopyFile(strBakFileName,m_strFileName,false);
	return bSuc ;
}

void CEx070202Dlg::OnScore() 
{
	UpdateData();
	Score();
}