HTTP Server Download file

header files and library files to include

#include <string>

#include <Wininet.h>

#include <fstream>

#pragma comment (lib, "Wininet.lib")

1. Open the server

int Chttp::createconnect (const string & httpserver,const String & username,const string &password,const int n Port)

{

DWORD err;
M_session = NULL;
M_connect = NULL;

Hinternet m_session = InternetOpen (L "AGENT", internet_open_type_preconfig,null,null,0);

if (m_session!) = NULL)

{

if (Httpserver.find ("www")!=string::npos)
{
M_connect = Internetconnecta (M_session, Httpserver.c_str (), Nport,username.c_str (), Password.c_str (), INTERNET_ service_http,0,0);
}
Else
{
M_connect = Internetconnecta (M_session, Httpserver.c_str (), Internet_default_http_port,username.c_str (), PASSWORD.C _str (), internet_service_http,0,0);
}

}

if (M_connect = = NULL)
{
Err = GetLastError ();

return op_fail;
}

return op_success;
}

2. Download the file

int chttp::D ownloadfile (const wstring & remotefilename,const wstring & Localpath,const wstring & LocalFilename)
{
if (M_connect = = NULL)
{
return op_fail;
}

Hinternet m_website = HttpOpenRequest (m_connect,l "GET", Remotefilename.c_str (), Http_version,null,0,internet_flag_ dont_cache| internet_flag_reload,0);

if (M_website = = NULL)
{
DWORD err = GetLastError ();

return op_fail;
}

BOOL bsendrequest=::httpsendrequest (m_website,null,0,0,0);

wchar_t achquerybuf[1024];

DWORD Dwquerybuflen = sizeof (ACHQUERYBUF);

BOOL Bquery=::httpqueryinfo (m_website,http_query_status_code,achquerybuf,&dwquerybuflen,null);

wstring str = ACHQUERYBUF;

if (m_pinitstruct! = NULL)
{
wchar_t querybuf[1024];
DWORD Querybuflen = sizeof (QUERYBUF);
BOOL Blquery=::httpqueryinfo (m_website,http_query_content_length,querybuf,&querybuflen,null);

wstring Buff = querybuf;
int length = _wtoi (Buff.c_str ());
}
if (!bquery)
{

return op_fail;
}

if (str = = L "$" | | str = = L "302")
{
Temporary file name

wstring tempfile = localpath+l\\package.tmp;

DeleteFile (Tempfile.c_str ());

FILE *fp_file = NULL;
DWORD err = _wfopen_s (&fp_file,tempfile.c_str (), L "WB");

DWORD number = 1;

DWORD maxblocksize = 512;
Char temp[512];

while (number)
{
memset (temp,0,512);

             if (! InternetReadFile (m_website,temp,maxblocksize-1,&number))
              {
                  fclose (Fp_file);
                 return Op_ FAIL;
            }
    
             fwrite (Temp, sizeof (char), number, fp_file);
         }
  
          fclose (fp_file);

Rename to target file
wstring desfile = LocalPath;

DeleteFile (Desfile.c_str ());

:: MoveFile (Tempfile.c_str (), Desfile.c_str ());

return op_success;
}
Else
{
return op_fail;
}
}

3. Shutting down the server

int Chttp::close ()
{
if (m_website! = NULL)
{
InternetCloseHandle (M_website);
}
if (m_connect! = NULL)
{
InternetCloseHandle (M_connect);
}

if (m_session! = NULL)
{
InternetCloseHandle (m_session);
}

return op_success;
}

HTTP Server Download file