Programmatically: How to create custom Magento event handlers

Step 1: Create a new module

Create a new directory for your module in app/code/local (or app/code/community if you want to share it with others). For example, let's create a module called MyCompany_MyModule.

Inside the MyCompany_MyModule directory, create the following files: etc/module.xml: This file defines the module and its dependencies. etc/config.xml: This file defines the configuration for your module. Model/MyEventHandler.php: This is where you'll put your event handler code.

Here's an example of what these files might look like:

	// app/code/local/MyCompany/MyModule/etc/module.xml


    MyCompany MyModule
    1.0.0
    My custom Magento module
    
        Magento_Core
    


// app/code/local/MyCompany/MyModule/etc/config.xml


    
        
            true
            local
        
    
    
        
            
            
                
                    
                
            
        
    


// app/code/local/MyCompany/MyModule/Model/MyEventHandler.php


class MyCompany_MyModule_Model_MyEventHandler
{
    public function __construct()
    {
        // Initialize your event handler
    }

    public function salesOrderPlaceAfter(Varien_Event_Observer $observer)
    {
        // Code to run when the order is placed goes here
        // You can access the order object using $observer->getEvent()->getOrder()
    }
}
	

Step 2: Register the event handler

In your config.xml file, we defined the event handler by adding the following code: