使用MFC提供的Http类下载和上传文件

1、下载文件
Download(const CString& strFileURLInServer, //待下载文件的URL
const CString & strFileLocalFullPath)//存放到本地的路径
{
 ASSERT(strFileURLInServer != "");
 ASSERT(strFileLocalFullPath != "");
 CInternetSession session;
 CHttpConnection* pHttpConnection = NULL;
 CHttpFile* pHttpFile = NULL;
 CString strServer, strObject;
 INTERNET_PORT wPort;

 DWORD dwType;
 const int nTimeOut = 2000;
 session.SetOption(INTERNET_OPTION_CONNECT_TIMEOUT, nTimeOut); //重试之间的等待延时
 session.SetOption(INTERNET_OPTION_CONNECT_RETRIES, 1);   //重试次数
 char* pszBuffer = NULL;  

 try
 {
  AfxParseURL(strFileURLInServer, dwType, strServer, strObject, wPort);
  pHttpConnection = session.GetHttpConnection(strServer, wPort);
  pHttpFile = pHttpConnection->OpenRequest(CHttpConnection::HTTP_VERB_GET, strObject);
  if(pHttpFile->SendRequest() == FALSE)
   return false;
  DWORD dwStateCode;

  pHttpFile->QueryInfoStatusCode(dwStateCode);
  if(dwStateCode == HTTP_STATUS_OK)
  {
    HANDLE hFile = CreateFile(strFileLocalFullPath, GENERIC_WRITE,
         FILE_SHARE_WRITE, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL,
         NULL);  //创建本地文件
   if(hFile == INVALID_HANDLE_VALUE)
   {
    pHttpFile->Close();
    pHttpConnection->Close();
    session.Close();
    return false;
   }
 
   char szInfoBuffer[1000];  //返回消息
   DWORD dwFileSize = 0;   //文件长度
   DWORD dwInfoBufferSize = sizeof(szInfoBuffer);
   BOOL bResult = FALSE;
   bResult = pHttpFile->QueryInfo(HTTP_QUERY_CONTENT_LENGTH,
           (void*)szInfoBuffer,&dwInfoBufferSize,NULL);

   dwFileSize = atoi(szInfoBuffer);
   const int BUFFER_LENGTH = 1024 * 10;
   pszBuffer = new char[BUFFER_LENGTH];  //读取文件的缓冲
   DWORD dwWrite, dwTotalWrite;
   dwWrite = dwTotalWrite = 0;
   UINT nRead = pHttpFile->Read(pszBuffer, BUFFER_LENGTH); //读取服务器上数据

   while(nRead > 0)
   {
    WriteFile(hFile, pszBuffer, nRead, &dwWrite, NULL);  //写到本地文件
    dwTotalWrite += dwWrite;
    nRead = pHttpFile->Read(pszBuffer, BUFFER_LENGTH);
   }

   delete[]pszBuffer;
   pszBuffer = NULL;
   CloseHandle(hFile);
  }
  else
  {
   delete[]pszBuffer;
   pszBuffer = NULL;
   if(pHttpFile != NULL)
   {
    pHttpFile->Close();
    delete pHttpFile;
    pHttpFile = NULL;
   }
   if(pHttpConnection != NULL)
   {
    pHttpConnection->Close();
    delete pHttpConnection;
    pHttpConnection = NULL;
   }
   session.Close();
    return false;
  }
 }
 catch(...)
 {
  delete[]pszBuffer;
  pszBuffer = NULL;
  if(pHttpFile != NULL)
  {
   pHttpFile->Close();
   delete pHttpFile;
   pHttpFile = NULL;
  }
  if(pHttpConnection != NULL)
  {
   pHttpConnection->Close();
   delete pHttpConnection;
   pHttpConnection = NULL;
  }
  session.Close();
  return false;
 }

 if(pHttpFile != NULL)
  pHttpFile->Close();
 if(pHttpConnection != NULL)
  pHttpConnection->Close();
 session.Close();
 return true;
}

2、上传文件
UploadFile(LPCTSTR strURL, //负责接收上传操作的页面的URL
LPCTSTR strLocalFileName)  //待上传的本地文件路径
{
 ASSERT(strURL != NULL && strLocalFileName != NULL);

 BOOL bResult = FALSE;
 DWORD dwType = 0;
 CString strServer;
 CString strObject;
 INTERNET_PORT wPort = 0;
 DWORD dwFileLength = 0;
 char * pFileBuff = NULL;

 CHttpConnection * pHC = NULL;
 CHttpFile * pHF = NULL;
 CInternetSession cis;

 bResult =  AfxParseURL(strURL, dwType, strServer, strObject, wPort);
 if(!bResult)
  return FALSE;
 CFile file;
 try
 {
  if(!file.Open(strLocalFileName, CFile::shareDenyNone | CFile::modeRead))
   return FALSE;
  dwFileLength = file.GetLength();
  if(dwFileLength <= 0)
   return FALSE;
  pFileBuff = new char[dwFileLength];
  memset(pFileBuff, 0, sizeof(char) * dwFileLength);
  file.Read(pFileBuff, dwFileLength);

  const int nTimeOut = 5000;
  cis.SetOption(INTERNET_OPTION_CONNECT_TIMEOUT, nTimeOut); //联接超时设置
  cis.SetOption(INTERNET_OPTION_CONNECT_RETRIES, 1);  //重试1次
  pHC = cis.GetHttpConnection(strServer, wPort);  //取得一个Http联接

  pHF = pHC->OpenRequest(CHttpConnection::HTTP_VERB_POST, strObject);
  if(!pHF->SendRequest(NULL, 0, pFileBuff, dwFileLength))
  {
   delete[]pFileBuff;
   pFileBuff = NULL;
   pHF->Close();
   pHC->Close();
   cis.Close();
   return FALSE;
  }
  DWORD dwStateCode = 0;
  pHF->QueryInfoStatusCode(dwStateCode);

  if(dwStateCode == HTTP_STATUS_OK)
   bResult = TRUE;
 }

 catch(CInternetException * pEx)
 {
  char sz[256] = "";
  pEx->GetErrorMessage(sz, 25);
  CString str;
  str.Format("InternetException occur!\r\n%s", sz);
  AfxMessageBox(str);
 }
 catch(CFileException& fe)
 {
  CString str;
  str.Format("FileException occur!\r\n%d", fe.m_lOsError);
  AfxMessageBox(str);
 }
 catch(...)
 {
  DWORD dwError = GetLastError();
  CString str;
  str.Format("Unknow Exception occur!\r\n%d", dwError);
  AfxMessageBox(str);
 }

 delete[]pFileBuff;
 pFileBuff = NULL;
 file.Close();
 pHF->Close();
 pHC->Close();
 cis.Close();
 return bResult;
}