Solved

How can I get error number from exception

Posted on 1998-08-10
4
301 Views
Last Modified: 2010-04-04
Earler with pascal the error code number was geven by IOResult function.
But in delphi with exception handling how can I get the last error number for example I/O errors code.
0
Comment
Question by:Motaz
  • 2
4 Comments
 
LVL 10

Expert Comment

by:viktornet
ID: 1361828
If I'm getting you right here is an example..otherwise give some more details please....thanx

var

  F: file of Byte;
begin
  if OpenDialog1.Execute then begin
    AssignFile(F, OpenDialog1.FileName);
    {$I-}
    Reset(F);
    {$I+}
    if IOResult = 0 then
      MessageDlg('File size in bytes: ' + IntToStr(FileSize(F)),
        mtInformation, [mbOk], 0);
    else
      MessageDlg('File access error', mtWarning, [mbOk], 0);
  end;
end;

Regards,
Viktor Ivanov
0
 
LVL 8

Accepted Solution

by:
ZifNab earned 10 total points
ID: 1361829
Hi Motaz,

 if you use exceptions for your IO control then the exceptions you get are of type EInOutError :

type
 EInOutError = class(Exception)
   ErrorCode: Integer;
 end;

So the ErrorCode give the same result as IOResult in early pascal days (or still in delphi for compatibility?)

try
 ...
except
 on E: Exception do showMessage('ErrorCode: ', E.ErrorCode);
end;

Zif.
0
 
LVL 7

Author Comment

by:Motaz
ID: 1361830
Thanks ZifNab, you are a porfull Delphi programmer. I hope I become like you. I search for this error number for a long time. Thanks again for your help. But there is some bugs in your code but it isn't important, that is the correction :

procedure TForm1.Button1Click(Sender: TObject);
var
     f:file;
begin
  try
    AssignFile(f,'NonExist.err');
    Reset(f);
    closefile(f);
  except
  on E: EinoutError do
    showMessage('ErrorCode: '+IntToStr(E.ErrorCode));
  end; (*** end try ***)

end;

Motaz.
0
 
LVL 8

Expert Comment

by:ZifNab
ID: 1361831
Motaz, ok correct, there is a bug! Thanks for letting me know. I did it by hand, so there was a possibility for a bug. Zif.
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

In this tutorial I will show you how to use the Windows Speech API in Delphi. I will only cover basic functions such as text to speech and controlling the speed of the speech. SAPI Installation First you need to install the SAPI type library, th…
In my programming career I have only very rarely run into situations where operator overloading would be of any use in my work.  Normally those situations involved math with either overly large numbers (hundreds of thousands of digits or accuracy re…
This tutorial gives a high-level tour of the interface of Marketo (a marketing automation tool to help businesses track and engage prospective customers and drive them to purchase). You will see the main areas including Marketing Activities, Design …
Along with being a a promotional video for my three-day Annielytics Dashboard Seminor, this Micro Tutorial is an intro to Google Analytics API data.

867 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

18 Experts available now in Live!

Get 1:1 Help Now