Download a file from the Internet with progress indicator

If you need to save the contents of a specified URL to a file - and be able to track the download progress, use the TDownLoadURL.

While TDownLoadURL is writing to the specified file, it periodically generates an OnDownloadProgress event, so that you can provide users with feedback about the process.

Here's an example - note that you must include the unit ExtActns in the uses clause. 

uses ExtActns, ...
type
  TfrMain = class(TForm)
  ...
  private
    procedure URL_OnDownloadProgress
       (Sender: TDownLoadURL;
        Progress, ProgressMax: Cardinal;
        StatusCode: TURLDownloadStatus;
        StatusText: String; var Cancel: Boolean) ;
  ...
implementation
...
procedure TfrMain.URL_OnDownloadProgress;
begin
  ProgressBar1.Max:= ProgressMax;
  ProgressBar1.Position:= Progress;
end;
function DoDownload;
begin
  with TDownloadURL.Create(self) do
  try
    URL:='http://z.about.com/6/g/delphi/b/index.xml';
    FileName := 'c:ADPHealines.xml';
    OnDownloadProgress := URL_OnDownloadProgress;
    ExecuteTarget(nil) ;
  finally
    Free;
  end;
end;
{
Note:
URL property points to Internet
FileName is the local file
}