Online-Update eines Programms..

[turboPASCAL]

Mein Vorschlag für das Versionsabfragedings:

Delphi-Quellcode:

uses WinINet;

const
  AppVersion = '1.00';
  DllVersion = '1.01';
  DatVersion = '3.10';

  URL        = 'http:\\www.MyPage.com\MyApps\MyAppVersion.vif';

function CopyFileFromURLToStream(const URL: string; MS: TMemoryStream): Boolean;
const
  BufferSize = 1024;
var
  hSession, hURL: HInternet;
  Buffer: array[0..BufferSize - 1] of Char;
  BufferLength: DWORD;
begin
  hSession := InternetOpen(PChar(Application.Title),
    INTERNET_OPEN_TYPE_PRECONFIG, nil, nil, 0);
  try
    Result := False;
    if Assigned(hSession) then
    begin

      hURL := InternetOpenURL(hSession, PChar(URL), nil, 0, 0, 0);
      try
        if Assigned(hURL) then
        begin
          MS.Position := 0;
          repeat
            InternetReadFile(hURL, @Buffer, BufferSize, BufferLength);
            MS.WriteBuffer(Buffer, BufferLength);
            { Application.ProcessMessages; }
          until BufferLength = 0;
          Result := True;
        end;

      finally
        InternetCloseHandle(hURL);
      end;
    end;
  finally
    InternetCloseHandle(hSession);
  end;
end;

function GetVerEntryString(MS: TMemoryStream; Key: String): String;
var
  i, p: Integer;
  sl: TStringList;
begin
  Result := '';

  if Assigned(MS) then
  begin
    sl := TStringList.Create;
    try
      sl.LoadFromStream(MS);
      for i := 0 to sl.Count - 1 do
      begin
        p := Pos(UpperCase(Key), UpperCase(sl.Strings[i]));
        if p > 0 then
        begin
          Result := Copy(sl.Strings[i], pos('=',sl.Strings[i])+1,
                      length(sl.Strings[i])-pos('=',sl.Strings[i]));
          break;
        end;
      end;
    finally
      sl.Free;
    end;
  end;
end;

procedure CheckOnlineFileUpdate;
var
  MemStream: TMemoryStream;
begin
  MemStream := TMemoryStream.Create;
  try
    CopyFileFromURLToStream(URL, MemStream);
    if Assigned(MemStream) then
    begin
      if GetVerEntryString(MemStream, 'MyAppVersion') = AppVersion then //...;
      if GetVerEntryString(MemStream, 'MyDllVersion') = DllVersion then //...;
      if GetVerEntryString(MemStream, 'MyDatVersion') = DatVersion then //...;
    end;

  finally
    MemStream.Free;
  end;
end;