Overriding Core File in Magento

Question

I am new magento and I want to override my "Data.php" file which is located at /app/code/core/Mage/Directory/Helper/Data.php

I want to remove the unwanted states from DropDownList.

Below is my Function in Data.php file

protected function _getRegions($storeId)
    {
        $countryIds = array();

        $countryCollection = $this->getCountryCollection()->loadByStore($storeId);
        foreach ($countryCollection as $country) {
            $countryIds[] = $country->getCountryId();
        }

        /** @var $regionModel Mage_Directory_Model_Region */
        $regionModel = $this->_factory->getModel('directory/region');
        /** @var $collection Mage_Directory_Model_Resource_Region_Collection */
        $collection = $regionModel->getResourceCollection()
            ->addCountryFilter($countryIds)
            ->load();

        $regions = array(
            'config' => array(
                'show_all_regions' => $this->getShowNonRequiredState(),
                'regions_required' => $this->getCountriesWithStatesRequired()
            )
        );

        foreach ($collection as $region) {
            if (!$region->getRegionId()) {
                continue;
            }

            //EOF Custom Logic Here
            $regions[$region->getCountryId()][$region->getRegionId()] = array(
                'code' => $region->getCode(),
                'name' => $this->__($region->getName())
            );
        }
        return $regions;
    }

In the above function I want to add code for removing the unwanted states from dropdown. I have added the code for this but when I am adding in the above function I am not getting any effect.

protected function _getRegions($storeId)
    {
        $countryIds = array();

        $countryCollection = $this->getCountryCollection()->loadByStore($storeId);
        foreach ($countryCollection as $country) {
            $countryIds[] = $country->getCountryId();
        }

        /** @var $regionModel Mage_Directory_Model_Region */
        $regionModel = $this->_factory->getModel('directory/region');
        /** @var $collection Mage_Directory_Model_Resource_Region_Collection */
        $collection = $regionModel->getResourceCollection()
            ->addCountryFilter($countryIds)
            ->load();

        $regions = array(
            'config' => array(
                'show_all_regions' => $this->getShowNonRequiredState(),
                'regions_required' => $this->getCountriesWithStatesRequired()
            )
        );
        $excludeRegions = array('AE','AA');
        foreach ($collection as $region) {
            if (!$region->getRegionId()) {
                continue;
            }

             //BOF Custom Logic Here
            ***$regionCode = $region->getCode();
            $this->_select->from(array('region'=>$this->_regionTable),
            array('region_id'=>'region_id', 'country_id'=>'country_id', 'code'=>'code', 'default_name'=>'default_name')
            )->where('code NOT IN (?)', $exclude_regions);***

            //EOF Custom Logic Here
            $regions[$region->getCountryId()][$region->getRegionId()] = array(
                'code' => $region->getCode(),
                'name' => $this->__($region->getName())
            );
        }
        return $regions;
    }

Even the whole Data.php file along with the above change i kept in local directory but it didn't work.

Answer 1

I don't encourage you to use this way of override, like creating app/code/local/Mage/Directory/Helper/Data.php, this is just the good way for spaghetti code..

1. Create a module Vids_Directory in pool local like app/code/local/Vids/Directory

2. Create app/etc/modules/Vids_Directory.xml and this code :

   <?xml version="1.0"?>
   <config>
       <modules>
           <Vids_Directory>
               <active>true</active>
               <codePool>local</codePool>
               <depends>
                   <Mage_Directory />
               </depends>
           </Vids_Directory>
       </modules>
   </config>
   

3. Create app/code/local/Vids/Directory/etc/config.xml and add this code :

   <?xml version="1.0"?>
   <config>
       <modules>
           <Vids_Directory>
               <version>0.1.0</version>
           </Vids_Directory>
       </modules>
       <global>
           <helpers>
               <directory>
                   <rewrite>
                       <data>Vids_Directory_Helper_Data</data>
                   </rewrite>
               <directory>
           </helpers>
       </global>
   </config>
   

4. Finally, you can create app/code/local/Vids/Helper/Data.php and add this :

   <?php
   
   class Vids_Directory_Helper_Data extends Mage_Directory_Helper_Data 
   {
       protected function _getRegions($storeId) {
           // Your code inside
       }
   }
   

Note : your code $this->_select->from... is referring to nothing, be careful (or probably you missed to add your complete code ?).

Hope it will help you :).