Window mobile 实现HTTP小文件下载

BOOL HttpDown(void)   
{
	HINTERNET hinternet = InternetOpen(_T("CartoType"),INTERNET_OPEN_TYPE_DIRECT,NULL,NULL,0);
	if (NULL == hinternet)
	{
		MessageBox(L"打开网络不成功",L"错误",MB_OKCANCEL);
		InternetCloseHandle(hinternet);
		return FALSE;
	}
	HINTERNET hfile = InternetOpenUrl(hinternet,(LPCTSTR)szURL,NULL,0,0,1);
	if (NULL == hfile)
	{
		MessageBox(L"打开网络地址不成功",L"错误",MB_OKCANCEL);
		InternetCloseHandle(hfile);
		InternetCloseHandle(hinternet);
		return FALSE;
	}
	char Buffer[32] = {0};
	DWORD BufLen = sizeof(Buffer);
	DWORD WIndex = 0;
	DWORD dwFileSize = 0;
	HttpQueryInfo(hfile,HTTP_QUERY_CONTENT_LENGTH   , Buffer, &BufLen, &WIndex);
	dwFileSize=(DWORD)_wtoi((wchar_t*)Buffer);
	CFile myFile;
	CFileException fileException;
	CString currentPath,fileName;
	GetCurrentDirectory(currentPath);
	if ( !myFile.Open (currentPath+fileName, CFile::modeCreate | CFile::modeReadWrite,
		&fileException ) )
	{
		MessageBox(L"创建文件不成功",L"错误",MB_OKCANCEL);
		return FALSE;
	}
	if (dwFileSize==0)
		dwFileSize=10000000;//设置个最大值
	DWORD tmp2=dwFileSize/100;
	DWORD currentFileSize=0;
	CString str;
	str.Format(_T("已下载%d%%"),0);
	DWORD dwSize;
	VOID * szTemp[25];
	do
	{
		if (!InternetReadFile (hfile, szTemp, 50,  &dwSize) )
		{
			myFile.Close();
			return FALSE;
		}
		if (!dwSize)
			break;  // Condition of dwSize=0 indicate EOF. Stop.
		else
		{
			myFile.Write(szTemp,dwSize);
			currentFileSize+=dwSize;
		}

		if ((currentFileSize/50)%(tmp2/50)==0)
		{
			lb.DeleteString(lb.GetCount()-1);
			str.Format(_T("已下载%d%%"),currentFileSize/tmp2);
		}
	}   // do
	while (TRUE);
	myFile.Close();
	InternetCloseHandle(hfile);
	InternetCloseHandle(hinternet);  
	return TRUE;
}