PHP 5 Re-assign $this PROBLEM - any ideas?

[Ryan White]

Hi all
Just a quickie, in case it's been covered, like a million times or
something.

I'm self taught, and thought I was being pretty clever when building a
"messaging" class.

The idea was to abstract "html email", "text email" and "sms message" up a
layer into a "message"

To get a message started, I call on something like this:

$msg = new Message("sms");

Message (which re-assigns the $this variable) then looks something like
this:

class Message{
var $message_hash;
var $message_path;//this can be changed, in case stuff is moved in future...
function ryan_Message($t ype=""){//starts the whole thing
switch($type){
case "html"://this means an html email
include_once("H tmlMessage.php" );
$this = new HtmlMessage();
break;
case "text"://this means a text mail
include_once("T extMessage.php" );
$this = new TextMessage();
break;
case "sms"://this means an sms message
include_once("S msMessage.php") ;
$this = new SmsMessage();
break;
}// end switch
}// end function
}// end class

Each class has methods that are named the same, but act a little
differently, so, basically, I can use the same set of commands to compose a
message and send it, regardless of what type of message it is.

Things work fantastically under php4, but I know that when I swap over to
php5, it's going to throw a hissy fit, because reassigning $this is not
allowed.

Aside from going around the Message class, and just starting messages of a
particular type from scratch:

Is there some sort of cunning retro-fit I could do to the Message class, so
I don't have to trawl through thousands of lines of code?

Any help much appreciated
Thanks
Ryan

[Wayne]

Re: PHP 5 Re-assign $this PROBLEM - any ideas?

On Thu, 16 Feb 2006 09:33:49 +0200, "Ryan White" <ryan@trigger.c o.za>
wrote:
[color=blue]
>Things work fantastically under php4, but I know that when I swap over to
>php5, it's going to throw a hissy fit, because reassigning $this is not
>allowed.
>
>Aside from going around the Message class, and just starting messages of a
>particular type from scratch:
>
>Is there some sort of cunning retro-fit I could do to the Message class, so
>I don't have to trawl through thousands of lines of code?[/color]

Use a factory method. Declare a public static method in the messaging
class that creates the appropriate type:

class Messge {
public static function factory($msgTyp e) {
... return the correct type here ...
}
}

Then just do a search & replace of all your 'new Message(' code and
replace it with 'Message::facto ry('...