Magento解决方法以避免编辑核心功能

Question

Hi have a function in app\code\core\Mage\Downloadable\Block\Adminhtml\Catalog\Product\Edit\Tab\Downloadable\Links.php

that its called when a user in admin panel enters in a downloadable product in catalog > product

The function its

 public function getConvertPDF(){

    $_prodId  = $this->getProduct()->getId();

    /*Validate if the product exist */

    if ($_prodId){
    $_proFile =$this->getLinkFile();

    $product = Mage::registry('current_product');
    if ($product->getTypeId() == 'downloadable') {
        $table = Mage::getModel('downloadable/link');
        $collection = $table->getCollection()->addProductToFilter($product->getId());
        foreach ($collection as $downloadable){
            $linkFile = $downloadable->getLinkFile();
            break;
        }
        $_proFile  = $linkFile;
    }

    $extencion = '.jpg';
    $path= 'C:/wamp/www/magento/media/downloadable/files/links';
    $pathout= 'C:/wamp/www/magento/media/catalog/product/small/';
    $test ='/small/';

     exec('convert '.$path.$_proFile.'[0] '.$pathout.$_prodId.$extencion);

/*-------------------------------------------------**/  


     $resource = Mage::getSingleton('core/resource');
     $adapter = $resource->getConnection('write');

     $bind = array(
            'value' => $test.$_prodId.$extencion
     );

     $where = array(
            'entity_id = ?'     => $_prodId,
            'attribute_id = ?'  => 86
     );

     $adapter->update($resource->getTableName('catalog_product_entity_varchar'), $bind, $where);

    }

    }

I saw a tutorial and they dont recomend to edit the core ... so my question its if there is way to make the same behavior , placing this function in other play , how should be the procedure?

Answer 1

Functions in magento can be override by creating the functionallity of core in local...

for example in these case

app\code\ local\Mage\Downloadable\Block\Adminhtml\Catalog\Product\Edit\Tab\Downloadable\Links.php

Update

The function should extends the core .. for example

extends Mage_Adminhtml_Block_Template