這個類還不錯的說,希望看到原文的請到CodeProject去看

http://www.codeproject.com/debug/logtrace.asp
下面我把原始碼放上來. /**/////////////////////////////////////////////////////////////////////////
// LogTrace.cpp -- Interface for the CLogTrace class
// A class to do debug logging

#ifndef __LOGTRACE_H__
#define __LOGTRACE_H__

class CLogTrace
{
// Construction/Destruction
public:
CLogTrace();
~CLogTrace();

// Attributes
public:
CString m_strAppName;

protected:
BOOL m_bActive;
CString m_strFileName;
BOOL m_bTimeStamp;

// Operations
public:
void WriteLine(LPCTSTR szLine);
void WriteLine(LPCTSTR szFormat, LPCTSTR szAddInfo);
void WriteLine(LPCTSTR szFormat, int nAddInfo);
void ResetFile();
void OnStartup(BOOL bActive, BOOL bTimeStamp);
void SetFileName(LPCTSTR szFileName);

protected:

 

// Inlines
public:
inline void SetActive(BOOL bSet)
{
m_bActive = bSet;
}
inline CString GetFileName()
{
return m_strFileName;
}
};

#endif // __LOGTRACE_H__

 

 

 

 

 

 

 

 

/**/////////////////////////////////////////////////////////////////////////
// LogTrace.cpp -- Implementation of the CLogTrace class

#include "stdafx.h"
#include <afxdisp.h>
#include "LogTrace.h"

/**//**************************************************

How to use CLogTrace

1. Make a static CLogTrace object as a member of the application class

2. Add the following lines to the InitInstance of the program

m_LogTrace.m_strAppName = "MyApp"; // use appropriate name here

m_LogTrace.SetFileName("Log.txt"); // sets the log file name and puts it in the exe path

m_LogTrace.OnStartup(TRUE, TRUE); // activates the log trace

3. Also in InitInstance, add the following line if you want to empty the log file
each time the application starts

m_LogTrace.ResetFile();

4. Any time you want to write to the log file, use the CLogTrace::WriteLine functions
these will write the text along with date and time

*******************************************************/

 

/**///////////////////////////////////////////////////////
// Construction/Destruction

CLogTrace::CLogTrace()
{
m_bActive = FALSE;
m_bTimeStamp = TRUE;

CString s;
}

CLogTrace::~CLogTrace()
{

}

/**/////////////////////////////////////////////////////////
// CLogTrace operations

void CLogTrace::ResetFile()
{
CStdioFile f;
CFileException fe;
CString s;

if (m_strFileName.IsEmpty()) return;

if (f.Open(m_strFileName, CFile::modeWrite | CFile::modeCreate, &fe) == FALSE)
{
return;
}

f.Close();
}

 

// bActive tells us if we want the trace to be active or not
// bTimeStamp tells us if we want time stamps on each line
// eliminating the time stamp allows us to use this class for a regular log file
void CLogTrace::OnStartup(BOOL bActive, BOOL bTimeStamp)
{
m_bActive = bActive;
m_bTimeStamp = bTimeStamp;
if (bTimeStamp == FALSE) return;
CString s;

// these ***'s help to indicate when one ru of the program ends and another starts
// because we don't always overwrite the file each time

WriteLine("/n/n******************************************/n/n");
s.Format("%s Log Trace %s/n/n", m_strAppName, COleDateTime::GetCurrentTime().Format());
WriteLine(s);
}

 

// function to write a line of text to the log file
void CLogTrace::WriteLine(LPCTSTR szLine)
{
CStdioFile f;
CFileException fe;
CString s;

if (m_bActive == FALSE) return;
if (m_strFileName.IsEmpty()) return;

if (f.Open(m_strFileName, CFile::modeWrite | CFile::modeCreate |
CFile::modeNoTruncate, &fe) == FALSE)
{
return;
}

try
{
f.SeekToEnd();
TRACE("LOGGIN %s/n", szLine);
if (m_bTimeStamp)
{
s.Format("%s/t%s/n", COleDateTime::GetCurrentTime().Format(),
szLine);
}
else
{
s.Format("%s/n", szLine);
}
f.WriteString(s);
}
catch (CException* e)
{
e->Delete();
}
f.Close();
}

// function to write a line of text, with an extra string
void CLogTrace::WriteLine(LPCTSTR szFormat, LPCTSTR szAddInfo)
{
if (m_bActive == FALSE) return;
CString s;
s.Format(szFormat, szAddInfo);
WriteLine(s);
}

// funtion to write a line of text with an extra integer
void CLogTrace::WriteLine(LPCTSTR szFormat, int nAddInfo)
{
if (m_bActive == FALSE) return;
CString s;
s.Format(szFormat, nAddInfo);
WriteLine(s);
}

// function to set the log file name. don't pass a fill path!
// just pass something like "log.txt"
// the file will be placed in the same dir as the exe file
void CLogTrace::SetFileName(LPCTSTR szFileName)
{
TCHAR drive[_MAX_PATH], dir[_MAX_PATH], name[_MAX_PATH], ext[_MAX_PATH];

const char *path = _pgmptr ;

_splitpath(path, drive, dir, name, ext);

m_strFileName.Format("%s%s%s", drive, dir, szFileName);

}