NYCPHP Meetup

[Brian D.]

Ben,

Chris Snyder gave a good example of why you want to use error
handling, but one other thing you may want to look at is the built-in
PHP Exception class. This article had some code samples:
http://www.phpbuilder.com/manual/en/language.exceptions.php

The example you gave with try_include() doesn't tell the user/developer:
- why it failed
- where it failed
- how important is the failure (is it fatal?)

All you know is that you got false back, now you have to figure out if
that's going to break something or not. Exceptions allow you to pass
back different types of failures, details about the failure, the level
of severity, and much more that you wouldn't get back from a
true/false return.

One of the most important things to consider, in my opinion, is that
exceptions are a *standardized* way to handle errors. This means that
when Joe returns a string that says "FAILURE" but Fred returned
"false", you don't always know what to expect. If an exception is
thrown, then you know for sure that something has failed and you need
to handle it.

- Brian




On Nov 28, 2007 1:04 PM, Ben Sgro (ProjectSkyLine)
<ben at projectskyline.com> wrote:
> Hello Kenneth,
>
> I saw an example similiar to this on PHP.net. I don't really
> see why try/catch is better ... Not trying to start a war here. -= ]
>
> function try_include( $filename )
> {
>     if( include($filename) != 1 )
>     {
>         echo "Problem trying to include file!";
>         return false;
>      }
>     return true;
> }
> ----- Original Message -----
> From: "Kenneth Downs" <ken at secdat.com>
> To: "NYPHP Talk" <talk at lists.nyphp.org>
>
> Sent: Wednesday, November 28, 2007 12:53 PM
> Subject: Re: [nycphp-talk] If/else vs Try/catch
>
>
> > Picture this example also:
> >
> > function try_include($filename) {
> >    try {
> >       include($filename);
> >    }
> >    catch Exception(e) {
> >       echo "Problem trying to include file!";
> >       return false;
> >    }
> >    return true;
> > }
> >
> > Ben Sgro (ProjectSkyLine) wrote:
> >> Hello Chris,
> >> Good points again. I've been doing some reading
> >> to get a better grasp on it.
> >>
> >> http://www.w3schools.com/php/php_exception.asp
> >>
> >> Seems to be a good explanation.
> >>
> >> Thanks.
> >>
> >> - Ben
> >>
> >> ----- Original Message ----- From: "csnyder" <chsnyder at gmail.com>
> >> To: "NYPHP Talk" <talk at lists.nyphp.org>
> >> Sent: Wednesday, November 28, 2007 11:38 AM
> >> Subject: Re: [nycphp-talk] If/else vs Try/catch
> >>
> >>
> >>> On Nov 28, 2007 11:25 AM, Ben Sgro (ProjectSkyLine)
> >>> <ben at projectskyline.com> wrote:
> >>>> Thanks. I'll read up on it now...and post my thoughts.
> >>>
> >>> Trying to explain the benefits of try/catch is like trying to explain
> >>> the benefits of OO code: you don't need it to get the job done, but it
> >>> really helps if you want to get the job done elegantly.
> >>>
> >>> If you find yourself writing code like:
> >>>
> >>> $success = $obj->process1();
> >>> if ( $success ) {
> >>>  $success = $obj->process2();
> >>>  if ( $success ) {
> >>>    $success = $obj->process3();
> >>>  }
> >>> }
> >>> if ( !$success ) {
> >>>  exit( "An error ocurred in either process 1, 2, or 3." );
> >>> }
> >>>
> >>> ... then try/catch is the way out of your nightmare.
> >>>
> >>> try {
> >>>  $obj->process1();
> >>>  $obj->process2();
> >>>  $obj->process3();
> >>> } catch Exception( e ) {
> >>>  exit( "An error occurred: ".$e->message() );
> >>> }
> >>>
> >>> Error handling doesn't need to be part of your program logic anymore.
> >>>
> >>> --
> >>> Chris Snyder
> >>> http://chxo.com/
> >>> _______________________________________________
> >>> New York PHP Community Talk Mailing List
> >>> http://lists.nyphp.org/mailman/listinfo/talk
> >>>
> >>> NYPHPCon 2006 Presentations Online
> >>> http://www.nyphpcon.com
> >>>
> >>> Show Your Participation in New York PHP
> >>> http://www.nyphp.org/show_participation.php
> >> _______________________________________________
> >> New York PHP Community Talk Mailing List
> >> http://lists.nyphp.org/mailman/listinfo/talk
> >>
> >> NYPHPCon 2006 Presentations Online
> >> http://www.nyphpcon.com
> >>
> >> Show Your Participation in New York PHP
> >> http://www.nyphp.org/show_participation.php
> >
> >
> > --
> > Kenneth Downs
> > Secure Data Software, Inc.
> > www.secdat.com    www.andromeda-project.org
> > 631-689-7200   Fax: 631-689-0527
> > cell: 631-379-0010
> >
> > _______________________________________________
> > New York PHP Community Talk Mailing List
> > http://lists.nyphp.org/mailman/listinfo/talk
> >
> > NYPHPCon 2006 Presentations Online
> > http://www.nyphpcon.com
> >
> > Show Your Participation in New York PHP
> > http://www.nyphp.org/show_participation.php
> _______________________________________________
> New York PHP Community Talk Mailing List
> http://lists.nyphp.org/mailman/listinfo/talk
>
> NYPHPCon 2006 Presentations Online
> http://www.nyphpcon.com
>
> Show Your Participation in New York PHP
> http://www.nyphp.org/show_participation.php
>



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