RE: RE: [DUG]: Freeing exceptions?

[Allan, Samuel]

Title: Message

Yes. Long story short, our three tier software reports exceptions on the server as strings which only contain the error message. On the client these are all raised as EDatabaseError. I want to send exception types from the server to the client. So we planned to change the server's SendClientException method (which just sends a string) to also include the class of the exception then use a Factory (or is it AbstractFactory, whatever Websnap uses for it's web modules, that style of thing) to create an exception of the right type on the client. However, there are places where the server's SendClientException is called when there is no existing exception object, just an error message. We want all exception strings recieved by the client to be in the same format to ease the unpacking burden.

 

Existing: SendClientException(msg: string);

 

We want:

 

SendClientException(msg: string); overload;

SendClientException(E: Exception); overload; // This does the work

 

So I wanted:

 

procedure SendClientException(msg: string);

var

   e: Exception;

begin

   e := Exception.Create(msg);

   try

      SendClientException(e);

   finally

      e.Free;

   end;

end;

 

Obviously this would be a bad place to raise an exception because it would never get sent to the client.

 

 

 

-----Original Message-----
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]
Sent: Monday, November 17 2003 8:48 a.m.
To: Multiple recipients of list delphi
Subject: RE: [DUG]: Freeing exceptions?

You are correct.

 

Can you tell us why you would want to create an exception object without raising it though?

 

Cheers,

 

C.

-----Original Message-----
From: Allan, Samuel [mailto:[EMAIL PROTECTED]
 

Exception decends from TObject. Correct me if I am wrong, but if I create an exception and do not raise it, I then have to free it? But if I create an exception, muck about with it, and then raise it I do not have to free it?

 

Is the below code a memory leak?

 

procedure TSam.Samuel;

var

  e: Exception;

begin

  e := Exception.Create('Foobar');

end;

 

Is the below code okay?

 

procedure TSam.TrySamuel;

var

  e: Exception;

begin

  e := Exception.Create('Foobar');

  try

    //do some stuff

  finally

    e.Free;

  end;

end;