AfterDownload callback procedure:

You can use the AfterDownload parameter to specify a callback procedure when you make the DwinsHs_CurPageChanged procedure call. The callback procedure will be executed when the download operation completes. Then the DwinsHs_CurPageChanged procedure returns.

Declaration:

type
  TAfterDownload = procedure (State: Integer);

Parameter:

• Satae: Integer:

  Contains the state code in integer. It can be one of the following values:

  • READ_OK (0): The download completes successfully.
  • CONNECT_ERROR_NETWORK (1): There is no Internet connection, or if all possible Internet connections are not currently active.
  • CONNECT_ERROR_OFFLINE (2): The computer is in offline mode.
  • CONNECT_ERROR_INITIALIZE (3): Failed to initialize the installation package for accessing Internet.
  • CONNECT_ERROR_OPENSESSION (4): Failed to open the FTP or HTTP session.
  • CONNECT_ERROR_CREATEREQUEST (5): Failed to create an HTTP request handle.
  • CONNECT_ERROR_SENDREQUEST (6): Failed to send request to the HTTP server.
  • READ_ERROR_DELETEFILE (7): The local file exists, and failed to delete it.
  • READ_ERROR_SAVEFILE (8): Failed to save data to the local file.
  • READ_ERROR_CANCELED (9): The download operation is terminated by user (the OnRead callback function returns false, or user clicks on the "Cancel" button or clicks on the window's Close button to exit the Setup wizard).
  • READ_ERROR_READDATA (10): Failed to read data from the remote URL.
  • Greater than or equal to 400: The HTTP status code.

Note:

The callback procedure will not be executed if the BeforeDownlaod callback function returns false, and the DwinsHs_CurPageChanged procedure will return immediately.

Example:

You can use the callback procedure to run, move or decompress files downloaded just now.

For example:

function BeforeDownload(): Boolean;
begin
  ...
  DwinsHs_AppendRemoteFile(ExpandConstant('{tmp}\abc.dll'), 'http://www.domain1.com/abc.dll',
    'My_Setup', rmGet, FILESIZE_QUERY_SERVER);
  ...
  DwinsHs_AppendMirrorFile(ExpandConstant('{tmp}\abc.dll'), 'http://www.domain2.com/abc.dll',
    'My_Setup', rmGet);
  ...
  Result := True;
end;
...
procedure AfterDownload(State: Integer);
begin
  ...
  if State = READ_OK then
    FileCopy(ExpandConstant('{tmp}\abc.dll'), ExpandConstant('{app}\abc.dll'), false);
  ...
end;
...
procedure CurPageChanged(CurPageID: Integer);
begin
  ...
  DwinsHs_CurPageChanged(CurPageID, @BeforeDownload, @AfterDownload);
  ...
end;

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