| Re: An overloading question [message #174492 is a reply to message #174483] |
Tue, 14 June 2011 22:27   |
sheldonlg
Messages: 166
Registered: September 2010
Karma:
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Senior Member |
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On 6/14/2011 2:32 PM, Denis McMahon wrote:
> On Tue, 14 Jun 2011 12:49:11 -0400, sheldonlg wrote:
>
>> I have a problem that I am wrestling with that should be so obvious and
>> easy -- but it isn't. I have a base class that has a method that calls
>> another method in the base class with $this->thatOtherMethod. I have
>> another class that extends the base class and I want to have
>> thatOtherMethod in the extended class override the one in the base
>> class. The calling method in the base class is called using and
>> instance of the extended class pointing to that method.
>>
>> Simply, here is an example:
>>
>> A.class.php
>> --------------------------
>> <?php
>> abstract class A {
>> public function b() {
>> $this->a();
>> }
>> protected function a() {
>> print 'In class A';
>> }
>> }
>> ?>
>>
>> B.class.php
>> ---------------------------
>> <?php
>> include_once 'A.class.php';
>> class B extends A {
>> public function a() {
>> print 'In class B';
>> }
>> }
>> ?>
>>
>> c.php
>> ----------------------------
>> <?php
>> include 'B.class.php';
>> $x = new B();
>> $x->b();
>> ?>
>> ----------------------------
>>
>> I want it to print out "In class B", but it prints out "In class A".
>>
>> I have looked over Google quite a bit and found nothing that helped. I
>> have tried making the methods public, protected, keep them both the same
>> access, etc. and have had no luck. Suggestions?
>
> I think A->a() is being used as a constructor for the base class when you
> instantiate the extended class.
>
> This might (or might not) be causing confusion as to what's happening.
>
> This code:
>
> <?php
>
> abstract class A {
>
> public function x() {
> print "x() In class A\n";
> $this->y();
> }
>
> public function y() {
> print "y() In class A\n";
> }
>
> public function a() {
> print "a() In class A\n";
> }
>
> }
>
> class B extends A {
>
> public function y() {
> print "y() In class B\n";
> }
>
> }
>
> print "instantiate\n";
>
> $x = new B();
>
> print "call function\n";
>
> $x->x();
>
> ?>
>
> gives:
>
> instantiate
> a() In class A
> call function
> x() In class A
> y() In class B
>
> Not sure, though, if that solves your problem or not?
>
> Rgds
>
> Denis McMahon
I modified B to give it an explicit constructor. It still didn't work.
Why did your example print out that last line. It was never called.
Why did it use it as a constructor? That doesn't seem to make sense.
--
Shelly
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