Custom error pages with templates in CodeIgniter

问题:

I'm using the template library for CodeIgniter, http://williamsconcepts.com/ci/codeigniter/libraries/template/reference.html, and now I want to implement custom error pages too. I found one method involving a MY_Router extending the default router: http://maestric.com/doc/php/codeigniter_404 but that only treats 404 errors. I want all errors to show a simple user-friendly page, including database errors etc, and I want it to go through a controller, partly so I can use the template library, and partly so I can also implement an email function to send myself information about the error that occurred.

Someone asked about extending the functionality of the above MY_Router method for other errors, like error_db, but got no answer from the author, so I'm turning here to see if anyone knows how to do this, along the lines of the above method or any other simple way of achieving it. Please note that I'm a newbie, so do not assume too much about my knowledge of basic CodeIgniter functionality :-)

回答1:

I've created an extension for the Exceptions class. In this extension I've replaced the $this->Exceptions->show_error(); method, witch is used by the show_error() function of CI.

when I call show_error('User is not logged in', 401); this custom method is looking for an error_$status_code file first. In the case of the example above, it will look for an error_401.php file.

When this file does not exists, it wil just load the error_general.php file, like the default $this->Exceptions->show_error(); does.

In your case, you can use the following code to use in your library, controller or whatever should throw an error.

<?php

if(!(isset($UserIsLoggedin))){
  $this->load->view('template/header');
  show_error('User is not logged in', 401);
  $this->load->view('template/footer');
}

?>

Your error_401.php file should than look like this:

<div id="container">
	<h1><?php echo 'This is an 401 error'; ?></h1>
	<?php echo $message; ?>
</div>

/application/core/MY_Exceptions.php:

<?php  if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class MY_Exceptions extends CI_Exceptions
{
	
	function show_error($heading, $message, $template = 'error_general', $status_code = 500)
	{		
		if((!isset($template)) || ($template == 'error_general')){
			if(file_exists(APPPATH.'errors/error_'.$status_code.'.php')) {
				$template = 'error_'.$status_code;
			}
		}    	
		
		if (!isset($status_code)) $status_code = 500;
		
		set_status_header($status_code);

		$message = '<p>'.implode('</p><p>', ( ! is_array($message)) ? array($message) : $message).'</p>';

		if (ob_get_level() > $this->ob_level + 1)
		{
			ob_end_flush();
		}
		ob_start();		
				
		include(APPPATH.'errors/'.$template.'.php');
		$buffer = ob_get_contents();
		ob_end_clean();
		return $buffer;
	}
	
}

?>

回答2:

I do it like this: I create my own error page, and whenever I should throw a 404 error, I actually load my 404 page.

So say my default controller is site.php, my site.php looks like this:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Site extends CI_Controller {

    public function index()
    {
        $this->load->view('welcome_message');
    }

    public function view($page = "home" , $function = "index")
    {
        do_something();
        if($status == "404")
        {
            $function = "404";
        }
        $this->load->view('templates/header', $data);
        $this->load->view($page.'/'.$function, $data);      
        $this->load->view('templates/footer', $data);
    }




}

/* End of file welcome.php */
/* Location: ./application/controllers/welcome.php */

So I serve the home/404.php whenever an error occurs. i.e., I don't allow CodeIgniter to call show_404(); therefore the 404 page looks like any other page.

p.s. I assume that you followed the nice tutorial in CodeIgniter's website.

回答3:

The simplest way to create custom error pages is to edit the files at /application/views/errors/html/error_*.php such as error_404.php (for 404s), error_db.php (for database errors) and error_general.php (for most other errors).

As these pages are within your application directory, you are free to customise them to your needs.

If your normal view template looks something like this:

<?php $this->load->view('includes/header'); ?>
...
...
<?php $this->load->view('includes/footer'); ?>

You can adapt this in your /application/views/errors/html/error_*.php files like so:

<?php
  $page_title = $heading;
  include VIEWPATH.'includes'.DIRECTORY_SEPARATOR.'header.php';
?>
<div class="well">
  <h1><?php echo $heading; ?></h1>
  <?php echo $message; ?>
</div>
<?php include VIEWPATH.'includes'.DIRECTORY_SEPARATOR.'footer.php'; ?>

Notice that we're no longer using views, but instead including the view files for the header & footer.

Another thing to note:

In the header view, I'm passing a $data object which includes $data['page_title']. As the error pages don't use views, you have to add any variables that you'd normally pass into the view, hence the presence of $page_title.

回答4:

config/routes.php 

edit

$route['404_override'] = '';

type here your controller for example Error

create a function index and load your view