Salesforce Platform Developer I Certification Guide

Validation rules and custom controllers

When a user enters data in your Visualforce page because your form is built with the apex:inputField tag and the data will be incorrect due to custom validation rules, you can display your (error) messages in your page using the apex:(page)messages tag. In the following example, we only define the field name and a Save button. If you don't enter a name, the validation will fail and you'll receive an error on your page.

The following code is for the custom controller:

public class MyCustomController {    private Movie__c movie;    public PageReference save() {        try{            update movie;        } catch(DmlException ex){            ApexPages.addMessages(ex);        }        return null;    }    public String getName() {        return 'MyController';    } public Movie__c ...