Using Extensions to Add Functionality - Visualforce

You have already used standard controllers, which provide a set of functionality such as automatic record retrieval, saving, and updating. Sometimes you will want more—perhaps you want to perform additional processing or record retrieval. You can do this by adding a controller extension, which is a custom Apex class that contains functionality that can be accessed from your Visualforce page.

Controller extensions are Apex classes that extend the functionality of a controller. They allow you to add methods that can be called from your Visualforce pages. A Visualforcepage can have more than one extension, and the same extension can be used in multiple Visualforce pages—providing another use case for extensions: as containers for additional functionality for sharing across a number of controllers.

Learning More

• The Apex Language Reference Guide documents the methods available in the StandardController class. This lesson uses getRecord(). Also available arecancel(), delete(), edit(), getId(), save(), and view().
• For an introduction to the Apex programming language, read the Apex Workbook.