DownloadFile('http://host.test/1.zip', 'C:\1.zip');

DownloadFile('https://host.test/1.zip', 'C:\1.zip');

function tFormUpdate.DownloadFile(const Url: string; const FileName : string): Boolean;

var

  NetHandle: HINTERNET;

  UrlHandle: HINTERNET;

  Buffer: array[0..1024] of char;

  BytesRead: cardinal;

  f : File;

begin

  NetHandle := InternetOpen(PChar(ExtractFileName(Application.ExeName)), INTERNET_OPEN_TYPE_PRECONFIG, nil, nil, 0);

 

  if Assigned(NetHandle) then begin

    UrlHandle := InternetOpenUrl(NetHandle, PChar(Url), nil, 0, INTERNET_FLAG_RELOAD , 0);

 

    if Assigned(UrlHandle) then begin

      AssignFile(f, FileName);

      Rewrite(F, 1);

      FillChar(Buffer, SizeOf(Buffer), 0);

      repeat

        FillChar(Buffer, SizeOf(Buffer), 0);

        InternetReadFile(UrlHandle, @Buffer, SizeOf(Buffer), BytesRead);

        pbUpload.Position := pbUpload.Position + Integer(BytesRead);

        Application.ProcessMessages;

        BlockWrite(f, Buffer, BytesRead);

      until BytesRead = 0;

      InternetCloseHandle(UrlHandle);

      CloseFile(F);

      REsult := true;

    end else begin

      Result := false;

    end;

    InternetCloseHandle(NetHandle);

  end else

    result := false;

end;