Posted by Jochem Maas on 10/21/39 11:22

axel wrote:
> Hello,
>
> following code won't work in the expected way:
>
> class ClassA {
> function getClassName() {
> return get_class($this); # [1]
> }
> }
> class ClassB extends ClassA { }
> echo ClassB::getClassName();
>
> this script echoes "Object" instead of "ClassB". but i would like to

either you tested some different code to what you posted above OR
(your build of?) 5.0.3 is borked.

I tested this on 5.0.2 and 5.0.4 and both did exactly what I expected, namely
output nothing - $this is not defined when you call ClassB::getClassName()
(because you make a static call) so nothing is the only logical output.

> return the classname of the derived class without writing the method again.
>
> this will work:

??? it's not even valid php.

>
> B = new ClassB();
> echo ClassB->getClassName();

maybe you mean:

class ClassA {function getClassName() { return get_class($this); }}
class ClassB extends ClassA {}
$B = new ClassB();
echo $B->getClassName();

which _does_ work but is fairly pointless because you
already know the classname in order to be able to create the object
in the first place.

>
>
> i tried to use line [2] instead of [1]
> return get_class(self); # [2]
> but this only returns an empty string.

again this is what I expect to happen.

>
> is there any solution for my problem?

I don't really see what the problem is, can you give some
more real world detail on what you are trying/want to do?

otherwise (re-)read this chapter:
http://php.belnet.be/manual/en/language.oop5.php

.... if you're _really_ into generic code then the reflection API
is maybe you should look into. I have used reflection no and again,
very useful stuff although to be honest I don't really grasp the
concept/reasoning behind reflection properly (which means I have probably
been 'misusing' it :-)

rgds

>
> i'm using PHP Version 5.0.3 (with Apache 1, Windows XP)
>
> greetings
> axel
>

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