Error handling in Yii is different than handling errors in plain PHP. First of all, Yii will convert all non-fatal errors to *exceptions*. By doing so, you can gracefully handle them using `try`-`catch`. Second, even fatal errors in Yii are rendered in a nice way. This means that in debugging mode, you can trace the causes of fatal errors in order to more quickly identify the cause of the problem.
The default Yii error page is great when developing a site, and is acceptable for production sites if `YII_DEBUG` is turned off in your bootstrap index.php file. But but you may want to customize the default error page to make it more suitable for your project.
The easiest way to create a custom error page it is to use a dedicated controller action for error rendering. First, you'll need to configure the `errorHandler` component in the application's configuration:
With that configuration in place, whenever an error occurs, Yii will execute the "error" action of the "Site" controller. That action should look for an exception and, if present, render the proper view file, passing along the exception:
After associating the class with the error as in the above, define the `views/site/error.php` file, which will automatically be used. The view will be passed three variables: