using cakephp, how do I handle model operations that return no results so my view doesn't break?
In my controller I have model operations that can return empty results. I've setup the view to display the results using a foreach loop. But if the model opertion is empty and returns no results then the foreach loop is breaking in my view.
This is the operation:
$match3 = $this->Draw->Match-> find('all',array('conditions'=>array('Match.draw_id'=>$id, 'Match.round_i开发者_开发百科d'=> 1, 'Match.match_position' => 3)));
What do I need to add to the model operation to return null? Or is null the best way to handle this?
If there is no data then I don't want anything displayed.
I did try this but got an undefined index error:
if (!$match3) return null; else return $match3;
Is there a best practice when it comes to handling empty model operations?
Much appreciated. -Paul
IMO, the "best practice" isn't CakePHP-specific. If your result set it empty, it's critical to inform your users of that fact. It's a simple test (in this case for an empty array as indicated by Travis) and a simple result. I typically do it like this in my views:
<?php if( empty( $match3 ) ): ?>
<h2>Display an appropriate empty set message.</h2>
<?php else: ?>
# do whatever you need to do to display the result set
<?php endif; ?>
If your find operation has no results, it will just return an empty array.
In your view, just put some logic to make sure that $match3 isn't an empty array before you output that section. E.g., in the view
<?php
// some code here to output part of the page
if( !empty( $match3 ) )
foreach( $match3 as $matches )
; // do something with $matches
// rest of your view code
?>
Very much depending on your app, the following responses may be appropriate:
$result = $this->Model->find(…);
if (!$result) {
// redirect to another page and display message
$this->Session->setFlash('No results found');
$this->redirect(array('action' => 'index'));
}
or
if (!$result) {
// throw a 404 (or any other) error
$this->cakeError('error404');
}
Again, this very much depends on the app and the action in question, especially a 404 should not be a standard response. In many cases it's probably best to handle it in the view as advised by Rob.
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