Visualforce Developer Guide

Introducing Visualforce
Tools for Visualforce Development
Getting a Quick Start with Visualforce
Customizing the Appearance and Output of Visualforce Pages
Standard Controllers
Standard List Controllers
Custom Controllers and Controller Extensions
What are Custom Controllers and Controller Extensions?
Build a Custom Controller
Building a Controller Extension
Building a Custom List Controller
Controller Methods
Controller Class Security
Working with Large Sets of Data
Considerations for Creating Custom Controllers and Controller Extensions
Order of Execution in a Visualforce Page
Order of Execution for Visualforce Page Get Requests
Order of Execution for Visualforce Page Postback Requests
Order of Execution Example
Test a Custom Controller
Validation Rules and Custom Controllers
Using the transient Keyword
Advanced Examples
Override Buttons, Links, and Tabs with Visualforce
Using Static Resources
Creating and Using Custom Components
Dynamic Visualforce Bindings
Dynamic Visualforce Components
Integrate Email with Visualforce
Visualforce Charting
Creating Maps with Visualforce
Render Flows with Visualforce
Templating with Visualforce
Developing Salesforce Apps with Visualforce
Adding Visualforce to a Salesforce AppExchange App
Using JavaScript in Visualforce Pages
Communicating Across the DOM with Lightning Message Service
Visualforce Best Practices
Standard Visualforce Component Reference
Appendices
PDF

Note: This release is in preview. Features described here don’t become generally available until the latest general availability date that Salesforce announces for this release. Before then, and where features are noted as beta, pilot, or developer preview, we can’t guarantee general availability within any particular time frame or at all. Make your purchase decisions only on the basis of generally available products and features.

Order of Execution in a Visualforce Page

When a user views a Visualforce page, instances of the controller, extensions, and components associated with the page are created by the server. The order in which these elements are executed can affect how the page is displayed to the user.

To fully understand the order of execution of elements on a Visualforce page, you must first understand the page's lifecycle–that is, how the page is created and destroyed during the course of a user session. The lifecycle of a page is determined not just by the content of the page, but also by how the page was requested. There are two types of Visualforce page requests:

  • A get request is an initial request for a page either made when a user enters an URL or when a link or button is clicked that takes the user to a new page.
  • A postback request is made when user interaction requires a page update, such as when a user clicks on a Save button and triggers a save action.

The maximum response size from a Visualforce page request must be below 15 MB.

Note