On Jul 31, 2008, at 1:49 PM, Jim Lucas wrote:
Philip Thompson wrote:
On Jul 30, 2008, at 1:29 PM, Jim Lucas wrote:
Marten Lehmann wrote:
Hello,
I'm using some php-classes which worked fine with php-5.0.4. Now
I tried to upgrade to php-5.2.6, but the classes give a lot of
errors. If I set
error_reporting(E_ALL);
I see messages like
Notice: Undefined property: FastTemplate::$main in /whereever/
inc.template.php on line 293
Notice: Undefined property: current_session::$cust_id in /
whereever/inc.init.php on line 117
In inc.template.php there are a lot of calls like $this->$key. In
inc.init.php there are calls like $session->cust_id.
to fix these errors, you would need to modify the code so it does
something like this.
where it calls $this->$key you need to check and make sure that
$key exists before you trying call for it.
So something like this would work.
if ( isset( $this->$key ) ) {
$this->$key;
} else {
$this->$key = null;
}
You didn't show any context in which you are using the above code.
So I don't know what will actually work in your situation. Show a
little more code that includes the method in which $this->$key is
called.
You will want to look at using the Overloading feature of PHP5.
Check out this page for overloading examples
http://us2.php.net/manual/en/language.oop5.overloading.php
Take note of the __get() and __set() methods. The __get method
checks to see if the key exists before it tries working with it.
Ok, I'm trying to understand the point to using these overloading
methods.
<?php
$obj = new ClassThatUsesOverloading ();
$obj->hi = 'Hi';
$obj->bye = 'Bye';
echo $obj->hi, ' ', $obj->bye;
// Output: Hi Bye
?>
I was only suggesting the overloading because it would be the
simplest thing to implement in an existing class without massively
re-write parts of your application.
You could simply add the __get() method and then have it check to
see if the value or $key existed before it tries using it. And if
it doesn't exist, then return null or something else. This would
get rid of a lot of your NOTICEs from PHP.
I would add a method something like the following to your class and
it should fix the problems with trying to access properties that do
not exist.
function __get($key) {
// Check for the existence of the key in object
if ( isset( $this->$key ) {
// If found, return value
return $this->$key;
}
// Default: return null
return null;
}
You could have done that or you could do the following.....
<?php
$obj = new ClassThatDoesntUseOverloading ();
$obj->setHi('Hello');
$obj->setBye('Bye Bye!');
echo $obj->hi(), ' ', $obj->bye();
// Output: Hello Bye Bye!
?>
This example is flawed by the fact that you are call hi and bye as a
method instead of referencing the property.
Wait a second. Isn't that the point of encapsulation and abstraction?
You don't have direct access to properties - only the class does
(well, if it's private).
~Phil
The 2nd way seems more *OOP* than the first - weird to explain. I
guess what I'm wanting to know is.... why would you use overloading
(in PHP)? The only reason I can think of is to avoid having to
create/use accessors. Please help me understand! But please be
nice! =D
Thanks,
~Philip
What has changed in php-5.2.x so that these calls don't work any
more? What is the new, required form to use objects in a similar
manner (unfortunately I have no ressources to code these classes
from scratch)? Thanks.
Kind regards
Marten
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