TWebBrowser crashes with embedded Youtube clips

StackOverflow https://stackoverflow.com/questions/8200581

Question

Here is my code:

type
  TForm1 = class(TForm)
    WebBrowser1: TWebBrowser;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  end;

implementation
uses ActiveX;

procedure TForm1.Button1Click(Sender: TObject); // method 1
var
  HtmlFile: string;
begin
  HtmlFile := ExtractFilePath(Application.ExeName) + 'test.html';
  WebBrowser1.Navigate(HtmlFile);
end;

procedure LoadHtml(wb: TWebBrowser; HTMLStr: string);
var
  aStream: TMemoryStream;
begin
  wb.Navigate('about:blank'); // reset the webbrowser
  while wb.ReadyState < READYSTATE_INTERACTIVE do // wait to load the empty page
    Application.ProcessMessages;
  if Assigned(wb.Document) then
  begin
    aStream := TMemoryStream.Create;
    try
      aStream.WriteBuffer(Pointer(HTMLStr)^, Length(HTMLStr));
      aStream.Seek(0, soFromBeginning);
      (wb.Document as IPersistStreamInit).Load(TStreamAdapter.Create(aStream));
    finally
      aStream.Free;
    end;
  end;
end;

procedure TForm1.Button2Click(Sender: TObject); // method 2
begin
  LoadHtml(WebBrowser1,
    '<html><head></head><body>'+
    '  <object width="640" height="390"> '+
    '  <param name="movie" value="http://www.youtube.com/v/L7NWdxFAHdY&hl=en_US&feature=player_embedded&version=3"> '+
    '  </param><param name="allowFullScreen" value="true"> '+
    '  </param><param name="allowScriptAccess" value="always"> '+
    '  </param><embed src="http://www.youtube.com/v/L7NWdxFAHdY&hl=en_US&feature=player_embedded&version=3" type="application/x-shockwave-flash" allowfullscreen="true" allowScriptAccess="always" width="640" height="390"> '+
    '  </embed></object> '+
    '</body></html>'
    );
end;

test.html

<object width="425" height="349">
<param name="movie" value="http://www.youtube.com/v/1hPxGmTGarM?version=3&amp;hl=iw_IL">
</param><param name="allowFullScreen" value="true"></param>
<param name="allowscriptaccess" value="always"></param>
<embed src="http://www.youtube.com/v/1hPxGmTGarM?version=3&amp;hl=iw_IL" type="application/x-shockwave-flash" width="425" height="349" allowscriptaccess="always" allowfullscreen="true">
</embed></object>

My application crashes in both methods. I get An unhandled win32 exception (caused by Flash player Exception EInvalidOp in module Flash10u.ocx at 00108657. Invalid floating point operation).

  • I tried this code on D5, D7, D9.
  • I tried to re-import SHDocVw.dll.
  • I also tried to use EmbeddedWB control instead of TWebBroser...
  • Internet Explorer/Avant/Maxthon has no problems with this HTML (all based on IE ActiveX).

Any suggestions or a fix?

How can I catch this error or even suppress it?

Is there a way to manipulate or change the HTML on the fly via a TWebBrowser event, so I can display an Image instead of the Flash player, same as Ad-Blockers works? (My customers have that code in their sites over the internet, and my Delphi application provides a fast preview)

UPDATE

I used a TTimer to enable/disable FPU (based on Arjen's idea):

function Get8087CW: Word; // for D5
asm
        PUSH    0
        FNSTCW  [ESP].Word
        POP     EAX
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
  Timer1.Enabled := False;
  Timer1.Interval := 5000; // 5 sec
  Saved8087CW := Get8087CW;
end;

procedure TForm1.WebBrowser1BeforeNavigate2(Sender: TObject;
  const pDisp: IDispatch; var URL, Flags, TargetFrameName, PostData,
  Headers: OleVariant; var Cancel: WordBool);
begin
  Timer1.Enabled := False;
  System.Set8087CW($133F); // Disable all fpu exceptions
end;

procedure TForm1.WebBrowser1DocumentComplete(Sender: TObject;
  const pDisp: IDispatch; var URL: OleVariant);
begin
   Timer1.Enabled := True;
end;

procedure TForm1.Timer1Timer(Sender: TObject);
begin
  Timer1.Enabled := False;
  Set8087CW(Saved8087CW);
end;

UPDATE (2)

I ended up masking the FPU exception in the application start-up. there was no (known) impact on my application ever since.

Was it helpful?

Solution

Try to disable temporarily FPU exception with Set8087CW(0x133f); info

OTHER TIPS

A bit more beautiful solution:

Math.SetExceptionMask([exInvalidOp, exDenormalized, exZeroDivide, exOverflow,
  exUnderflow, exPrecision]);

If I read documentation correct, Math.SetExceptionMask silences every exception mentioned.

However, it is just cleaner and more beautiful version of @Arjen's approach.

Licensed under: CC-BY-SA with attribution
Not affiliated with StackOverflow
scroll top