c++记录日志到txt

int WriteLog(string msg)
{
    SYSTEMTIME sys;
    GetLocalTime( &sys ); //取系统时间
    CString strtemp;
    strtemp.Format("%d-%d-%d %d:%d:%d::%d :",sys.wYear,sys.wMonth,sys.wDay,sys.wHour,sys.wMinute,sys.wSecond,sys.wMilliseconds);
    string dtime((LPCSTR)strtemp);

    ofstream outfile ;
    outfile.open("d:\\LOG.txt",ios::app); //文件的物理地址，文件的打开方式
    int m=0;
    if(outfile.is_open())  
    {  
     outfile<<dtime<<msg<<"\n"; 
     outfile.close();  
     return 0;
    }
    else
    {
     return 1;
    }
} 

读取txt文件：

    ifstream infile ("d:\\LOG.txt");
    string line;  
    if(infile)
    {
        while(getline(infile,line))
        {
             cout << line << endl;  
        }
    }