log文件的读写[转]

/**   * 用于输出log文件的类.   */    #ifndef LOG_H    #define LOG_H    //log文件路径  #define LOG_FILE_NAME "log.txt"  //启用开关  #define LOG_ENABLE  #include <fstream>    #include <string>    #include <ctime>    using namespace std;    class CLog    {    public:        static void GetLogFilePath(CHAR* szPath)      {          GetModuleFileNameA( NULL, szPath, MAX_PATH ) ;          ZeroMemory(strrchr(szPath,_T('\\')), strlen(strrchr(szPath,_T('\\') ) )*sizeof(CHAR)) ;          strcat(szPath,"\\");          strcat(szPath,LOG_FILE_NAME);      }      //输出一个内容，可以是字符串(ascii)、整数、浮点数、布尔、枚举      //格式为：[2011-11-11 11:11:11] aaaaaaa并换行      template <class T>      static void WriteLog(T x)      {          CHAR szPath[MAX_PATH] = {0};          GetLogFilePath(szPath);          ofstream fout(szPath,ios::app);          fout.seekp(ios::end);          fout << GetSystemTime() << x <<endl;          fout.close();      }      //输出2个内容，以等号连接。一般用于前面是一个变量的描述字符串，后面接这个变量的值      template<class T1,class T2>       static void WriteLog2(T1 x1,T2 x2)      {          CHAR szPath[MAX_PATH] = {0};          GetLogFilePath(szPath);          ofstream fout(szPath,ios::app);          fout.seekp(ios::end);          fout << GetSystemTime() << x1 <<" = "<<x2<<endl;          fout.close();      }      //输出一行当前函数开始的标志,宏传入__FUNCTION__      template <class T>      static void WriteFuncBegin(T x)      {          CHAR szPath[MAX_PATH] = {0};          GetLogFilePath(szPath);          ofstream fout(szPath,ios::app);          fout.seekp(ios::end);          fout << GetSystemTime() << "    --------------------"<<x<<"  Begin--------------------" <<endl;          fout.close();      }      //输出一行当前函数结束的标志，宏传入__FUNCTION__      template <class T>      static void WriteFuncEnd(T x)      {          CHAR szPath[MAX_PATH] = {0};          GetLogFilePath(szPath);          ofstream fout(szPath,ios::app);          fout.seekp(ios::end);          fout << GetSystemTime() << "--------------------"<<x<<"  End  --------------------" <<endl;          fout.close();      }  private:      //获取本地时间，格式如"[2011-11-11 11:11:11] ";       static string GetSystemTime()        {            time_t tNowTime;            time(&tNowTime);            tm* tLocalTime = localtime(&tNowTime);            char szTime[30] = {'\0'};            strftime(szTime, 30, "[%Y-%m-%d %H:%M:%S] ", tLocalTime);            string strTime = szTime;            return strTime;        }    };    #ifdef LOG_ENABLE  //用下面这些宏来使用本文件  #define LOG(x)              CLog::WriteLog(x);          //括号内可以是字符串(ascii)、整数、浮点数、bool等  #define LOG2(x1,x2)     CLog::WriteLog2(x1,x2);  #define LOG_FUNC        LOG(__FUNCTION__)               //输出当前所在函数名  #define LOG_LINE        LOG(__LINE__)                       //输出当前行号  #define LOG_FUNC_BEGIN  CLog::WriteFuncBegin(__FUNCTION__);     //形式如：[时间]"------------FuncName  Begin------------"  #define LOG_FUNC_END     CLog::WriteFuncEnd(__FUNCTION__);      //形式如：[时间]"------------FuncName  End------------"  #else  #define LOG(x)                #define LOG2(x1,x2)       #define LOG_FUNC          #define LOG_LINE          #define LOG_FUNC_BEGIN    #define LOG_FUNC_END      #endif  #endif