long GetFileLength(string strPath)
{
    long lSize = 0;
    ifstream fin(strPath.c_str(), ios::in | ios::binary);
    char szBuf[1024*1000] = "";
    while (fin.read(szBuf, 1024 * 1000 - 1))
    {
        lSize += strlen(szBuf);
        memset(szBuf, 0, 1024*1000);
    }
    fin.close();
    lSize += strlen(szBuf);
    return lSize;
}

long GetFileLength(string strPath)
{
    
    ifstream fin(strPath.c_str(), ios::in | ios::binary);
    fin.seekg(0, ios_base::end);
    streampos pos = fin.tellg();
    long lSize = static_cast<long>(pos);
    fin.close();
    return lSize;
}