Magento: Show Optgroup in select box

Here Furniture is OptGroup. Copy and paste in any PHTML file and check the output.

$options = array(0=>array('label' => 'Furniture',

                          'value' => array

                            (

                                0 => array

                                (

                                    'label' => 'Chair',

                                    'value' => 1

                                ),

                                1 => array

                                (

                                    'label' => 'Couch',

                                    'value' => 2

                                )

                            )

                        )

                    );

$tmp = Mage::app()->getLayout()->createBlock('core/html_select')

            ->setName('product_id')

            ->setId('product_id')

            ->setTitle('products')

            ->setClass('validate-select');

$select =  $tmp->setOptions($options);

echo $select->getHtml();

Magento: Get Child Categories by Category ID

  

$category_model = Mage::getModel('catalog/category'); //get category model

$_category = $category_model->load($categoryid); //$categoryid for which the child categories to be found       

$all_child_categories = $category_model->getResource()->getAllChildren($_category); //array consisting of all child categories id




OR


$children = Mage::getModel('catalog/category')->getCategories(4);

//4 is parent category ID
foreach ($children as $category) {
    echo $category->getName();
}

Captcha Extensions for Magento Forms to control Spam submissions

http://www.magentocommerce.com/magento-connect/Fontis/extension/1169/fontis-recaptcha

http://www.fontis.com.au/magento/extension/recaptcha

http://www.magentocommerce.com/magento-connect/outsourceonline-captcha-6034.html

https://store.i95dev.com/i95dev-captcha.html

Json Encode and Decoding in Magento

Json Encode an Array in Magento
$json = Mage::helper('core')->jsonEncode($array);

Json Decode in Magento
 $array = Mage::helper('core')->jsonDecode($jsonString);

Transactional Email Preview Showing HTML code in Magento 1.6.2.0

This issue exists in Magento version 1.6.2.0. To fix the issue follow below steps.

1. Copy app/code/core/Mage/Adminhtml/Block/System/Email/Template/preview.php file to app/code/local/Mage/Adminhtml/Block/System/Email/Template/preview.php
2. Comment the following lines of code (Starts at line number 47) in protected function _toHtml() method

      $template->setTemplateText(
            $this->escapeHtml($template->getTemplateText())
        );

Get first Image from Post content in Wordpress

Add this function to functions.php at bottom

function catch_that_image() {
  global $post, $posts;
  $first_img = '';
  ob_start();
  ob_end_clean();
  $output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches);
  $first_img = $matches[1][0];

  if(empty($first_img)){ //Defines a default image
    $first_img = "/images/default.jpg";
  }
  return $first_img;
}

Below code will display image URL from content of the post 

<?php echo catch_that_image(); ?>

Magento: Log & Cache Maintenance Script

http://www.magentocommerce.com/wiki/groups/227/maintenance_script

http://www.crucialwebhost.com/kb/article/log-cache-maintenance-script/

Change Wordpress Theme Dynamically / Programatically

Apply default theme if the visitor browser is IE 6:
http://www.nathanrice.net/blog/serve-ie6-visitors-the-default-wordpress-theme/

Plug-in to identify the Mobile devise and apply selected theme:
http://code.kuederle.com/browserbasedthemes

Some More Plug-ins:
http://wordpress.org/extend/plugins/wordpress-mobile-pack/screenshots/
http://wordpress.org/extend/plugins/wptouch/