oop stuff.

atmorell

Hello.

I have an object (basic) with some standard methods I have created - e.g. delete, create, print etc. This object is used to initialize my tables, so I don't have to create the boring forms and tables for create, delete and view what is in the sql table. Inside the object there is a large case method that checks the variable $action and jumps to the correct method. If I click on a delete link the object automatic jumps to the method that deletes the correct row. All this is fine, and saves me a lot of time. However how can I customize this object for each instance? Let’s say I want to have the create method slightly modified for my cars instance. Can I e.g. append another class to the basic class, so that my methods in my cars class overrule the method in my basic class? – If my cars class has a create method it should replace the create method in my basic class. All other methods in my basic object should still work. (Not them that is replaced)

This is an example for my case statement.
…
case 'delete':
$this->delete();
break;

Best regards.
Asbjørn Morell.

msound

You could has the car class extend your basic class so that it has access to all of the basic methods. To modify the method in the car class you just re-create the function and create a car object. The car object should use the modify methods while your basic objects will still use the original methods.

To customize methods I usually just pass a variable through to them. Instead of:

$this->delete();

you could use:
$this->delete('basic');
and
$this->delete('car');

Then in the delete method itself you could have another case switch that looks at the variable passed through and then performs the appropriate function.

Installer

Example of what msound said:

class Class_1
{  

    function show() { 
        echo 'Class_1';
    }
}

class Class_2 extends Class_1
{  

    function show() {
        echo 'Class_2';
   }
}

$c2 = new Class_2;
$c2->show();
// Class_2

The calling object's method is used.

msound

Example of what msound said:

Thanks! that does make it a lot easier to understand. 🙂

atmorell

This is great stuff 🙂 Thank you guys.
However how can I modify the class_1.show method without replacing it completely? I don’t want a large case statement in the class_1.show method. Let's say that if class_2 extends class_1. It should echo 'ClassBANG_1' do some code - and call a different method than the default. The reason I want this is because I am going to be using this method for many different projects.

Best regards.
Asbjørn Morell.

thorpe

Do you meen like?

<?php

class Class_1 
{  
    function show() {
        echo 'Class_1';
    }       
}

class Class_2 extends Class_1 
{  
    function show() {
        parent::show();
        echo 'Class_2';
    }       
}

   $c2 = new Class_2;
   $c2->show();

?>

atmorell

hmmm.. does this only append to the end of class_1 method show? I wan't to change something in the code in class_1 show.

Like this:

before.
echo 'Class_1';

after.
echo 'this is great';
echo 'Class_BANG_1';
$this->delete();

thorpe

This doesn't sound right to me. Can you post your actual code, and explain what it is your trying to do?

I meen you could just...

class Class_2 extends Class_1
    {  

        function show() {
            echo "foo";
            parent::show();
            echo 'Class_2';
        }       

    }

But does that really help?

atmorell

It is theory for now. I am going to use class_1 for many different projects. And I would like to change a few things in the class_1 show method without affection my other projects.

Installer

This might be where variables and function arguments would come in handy. For example:

class Class_1 
{   

    function show($var = 'Class_1') 
    { 
        echo 'Class_1 from ' . $var; 
    } 
} 

class Class_2 extends Class_1 
{   

    function show($var = 'Class_2') 
    { 
        parent::show($var); 
    } 
} 

$c1 = new Class_1; 
$c1->show();
// Class_1 from Class_1 
$c2 = new Class_2; 
$c2->show(); 
// Class_1 from Class_2