Ajax call not returning a response, just reloads page - ajax

Question

I have a Symfony 3 CRM and I use ajax calls to action the removal of items throughout the system. It uses a single call and then uses a switch statement to determine what it is the user is attempting to delete and handles it accordingly.
However, for some strange reason one particular type of item doesn't seem to work, it just reloads the page.
Here is the trigger button (I am implementing bootstrap confirmation):
<a href="" data-type="unit" id="{{ unit.id }}"
data-toggle="confirmation-singleton"
data-btn-ok-class="btn btn-xs btn-success"
data-btn-cancel-class="btn btn-xs btn-danger"
class="btn btn-xs btn-danger remove-item">
<i class="fa fa-remove no-override"> </i>
</a>
My ajax call for removal of items:
$('.remove-item').confirmation({
rootSelector: '[data-toggle=confirmation-singleton]',
container: 'body',
onConfirm: function() {
var type = $(this).attr('data-type');
var id = $(this).attr('id');
var data = type + '|' + id;
$.ajax( '/app_dev.php/ajax-call/remove-item/' + data )
.done( function(response) {
if(response != 'success') {
if(response == 'units_exist') {
alert("You cannot delete this item as there are units already linked to it.");
} else if(response == 'no_property') {
alert("Sorry! Property could not be found.");
} else if(response == 'bookings_exist') {
alert("Sorry! This unit has bookings. Please delete the bookings first.");
}
}
});
return false;
},
onCancel: function() {
return false;
}
});
And on the PHP side, for this particular example:
$data = $request->get('data');
$parts = explode("|",$data);
$type = $parts[0];
$id = $parts[1];
// using switch on $type
case 'unit':
$em = $this->getDoctrine()->getManager();
$repo = $em->getRepository('AppBundle:Unit');
$booking_repo = $em->getRepository('AppBundle:Booking');
$bookings = $booking_repo->findBy(array('unitId' => $id)); // check to see if any bookings exist
if(!empty($bookings)) {
return new Response('bookings_exist');
} else {
$item = $repo->findOneBy(array('id' => $id));
if(!empty($item)) {
$em->remove($item);
$em->flush();
}
}
break;
In this example, it SHOULD return 'bookings_exist' and if I directly go to the URL in the browser, it does display this message - however, all it does it reload the page instead of throwing the alert as stipulated in the ajax call. I know this call works as it does successfully delete other items in the CRM, it just seems to be when it cannot delete it due to a condition such as this.
I may be missing something really obvious here, so any help is appreciated.

Answer 1

For jQuery Ajax, use success and error handlers
Other handlers in jQuery's Ajax object are unreliable at best, and vary in their behavior and support between versions and browsers.
Prevent Default is generally a good idea with ajax handled events
Should jQuery fail, and NOT return false, the element will do it's default behavior, which in your case is which reloads the page.
onConfirm: function(e) {
e.preventDefault();
var type = $(this).attr('data-type');
var id = $(this).attr('id');
var data = type + '|' + id;
$.ajax( '/app_dev.php/ajax-call/remove-item/' + data )
.success( function(response) {
if (response.errorMessage) {
alert(response.errorMessage);
}
})
.error( function(xhr, status, error) {
console.log(status + '\n' + error);
})
;
return false;
}
PHP Side, build a JSONResponse
if(!empty($bookings)) {
return new JsonResponse([
'errorMessage' => 'Sorry! Property could not be found.'
);
}

Answer 2

instead of just adding .done() you should also use
.fail(function( jqXHR, textStatus, errorThrown ) {});
to catch any errors.

Answer 3

If the bookings is not empty then the function will return the new response 'booking_exist' and stop ... it will not proceed to next statments .
So if you need to delete the item use this code instead :
if(empty($bookings)) {
return new Response('bookings_not_exist');
} else {
$item = $repo->findOneBy(array('id' => $id));
if(!empty($item)) {
$em->remove($item);
$em->flush();
}