How do I overwrite core functions?

[Marked13]

Hi there

Been working on a big project with a bunch of modifications. For some of these modifications I have been overwriting core files but copying entire PHP classes/files from core to the local directory. But... I only want to overwrite one or two functions from these classes.

For example and in particular I want to overwite some functions of the admin order create class:

class Mage_Adminhtml_Model_Sales_Order_Create extends Varien_Object implements Mage_Checkout_Model_Cart_Interface 

From my limited knowledge in this area, I think I have to do something like

class my_new_class extends Mage_Adminhtml_Model_Sales_Order_Create

function function_to_overwrite(){}

But.... how I can implement this new class so that it runs to overwrite the core function?

Thanks in advance

Mark

[MrKhoa99]

Hello,

You can google how to rewrite model, block, to name just a few.
If you use PHPStorm editor, you should install Magicento Plugin. It will help you overwriting classes quickly.
We should use Observer to minimize our core customization.

In your example:

Your config xml should add:

        <models>
            <adminhtml>
                <rewrite>
<sales_order_create>Your_new_rewrite_class</sales_order_create>
                </rewrite>
            </adminhtml>
        </models>

You can create your new Model class under your Model folder, example: Model/Adminhtml/Sales/Order/Create.php