Internet File Download

BOOL DownloadHttpFile(LPCSTR szDomainAddr, LPCSTR szInetFileAddr, LPCSTR szDownloadPath)
{
	if (!szDomainAddr || !szInetFileAddr || !szDownloadPath)
		return FALSE;

	// 1. Create Session
	CInternetSession session;
	CHttpConnection* pHttpConn = session.GetHttpConnection(szDomainAddr);
	if (NULL == pHttpConn)
		return FALSE;

	// 2. Open Internet File
	CHttpFile* pHttpFile = (CHttpFile*)session.OpenURL(szInetFileAddr, 1, INTERNET_FLAG_TRANSFER_BINARY|INTERNET_FLAG_RELOAD);
	if (pHttpFile)
	{
		// 3. Create Download File to Local
		CFile downloadFile;
		if (downloadFile.Open(szDownloadPath, CFile::modeCreate | CFile::modeWrite))
		{
			DWORD dwInetFileSize = 0;
			pHttpFile->QueryInfo(HTTP_QUERY_CONTENT_LENGTH, dwInetFileSize);

			// 4. Download
			// Check Total File Size : do - while
			// Check Trans Size : while (TRUE)
			do 
			{
				downloadFile.SeekToBegin();
				pHttpFile->SeekToBegin();
				
				while (TRUE)
				{

					ULONGLONG lnChunkSize = pHttpFile->GetLength();
					if (lnChunkSize == 0)
						break;

					BYTE* pBuffer = new BYTE[(UINT)lnChunkSize + 1];
					DWORD dwReadSize = pHttpFile->Read(pBuffer, (UINT)lnChunkSize);

					if (dwReadSize > 0)
						downloadFile.Write(pBuffer, dwReadSize);

					delete pBuffer;
				}
			}
			while (dwInetFileSize != downloadFile.GetLength());

			downloadFile.Close();
		}

		pHttpFile->Close();
		delete pHttpFile;
	}

	pHttpConn->Close();
	delete pHttpConn;

	return TRUE;
}

* Session 및 File의 Close 주의