How to redirect class from Block?

Question

Magento

good day to everyone who can explain right on the fingers, I want to make changes to the module from the core bundle which, and I want to make changes to the file app/code/core/Mage/Bundle/Block/Catalog/Product/View/Type/Bundle/ /option.php
How can I make magento take a function from my file in local? for the first time I work on magento, I read a couple of articles, but everywhere there are examples on controllers, is it possible to do it the way I thought?

Answer 1

There are several options, the simplest is rewriting the class.
You create your own module and add to config.xml

<blocks>
            <my_ext>
                <class>My_Ext_Block</class>
            </my_ext>
            <bundle>
                <rewrite>
                   <catalog_product_view_type_bundle_option>My_Ext_Block_Catalog_Product_View_Type_Bundle_Option</catalog_product_view_type_bundle_option>
                </rewrite>
            </bundle>
        </blocks>

You create your block, which is inherited from the core block and you can override any methods you want