Form submitted twice in Chrome/Safari

Question

Dear Stackoverflow,

I am seeking to perform a basic form post, but the following submits to the server twice in Chrome and Safari (but behaves as expected in Firefox):

<form id="create-deck-form" action="/decks/create" method="post">
  <fieldset>
    <legend>Create new deck</legend>
    <label for="deck-name-field">Name</label>
    <input id="deck-name-field" name="deck-name-field" type="text" value="" maxlength="140" />

    <label for="tag-field">Tags</label>
    <input id="tag-field" name="tag-field" type="text" value="" maxlength="140" />

    <input class="add-button" type="submit" value="Create" />
  </fieldset>
</form>

I would like to use the onsubmit attribute to perform validation on the fields before submission, but wherever the return value is true, the form is submitted twice.

I have sought to bind a jQuery handler to the form, but here too, where the default behaviour is not prevented, the form is submitted twice, e.g.:

<script type="text/javascript">
 $(document).ready(function() {
     $("#create-deck-form").submit(function(event){
          if($("#deck-name-field").val() == "") {
            event.preventDefault();
            alert("deck name required");
          }
        });
 });
</script>

While I suppose there is something blindingly obvious wrong here to a fresh pair of eyes, I am deeply confused why submission, with or without validation, makes a duplicate post to the server in Chrome and Safari. I'd be grateful for any insight.

Answer 1

Can you try return false; after your alert and remove event.preventDefault();. Maybe you also need return true; in your else-clause. I believe I have that working somewhere.

Answer 2

I'm not 100% sure, but please try this one:

<script type="text/javascript">
   $(document).ready(function() {
      $("#create-deck-form").submit(function(event){
         if(!$("#deck-name-field").val().length) {
           return false;
         }
       });
   });
</script>

if that does not work, please have a look at

for(e in $("#create-deck-form").data('events'))
    alert(e);

This will alert you all events which are bound to your form. Maybe there are more event handlers? Otherwise also alert/log

$("#create-deck-form").attr('onclick')

and

$("#create-deck-form").attr('onsubmit')

just in case.

Answer 3

Ok, not sure how much this will help, but try removing the submit input and submitting the form via javascript. So for instance

<input id="submit-button" class="add-button" type="button" value="Create" />

Then instead of listening to the onsubmit, you can try

$('#submit-button').click(function(evt) {
    if(validationSuccess(...)) {
        $("#create-deck-form").submit();
    } else {
        //display whatever
    }
});

Now you're way should work too... but this way you can debug where you're problem is.... This should only submit once... good luck!

Answer 4

This issue is actually associated with Facebox (http://defunkt.github.com/facebox/). Facebox initialization causes a second set of requests after your page loads. So, if you post to /myaction/create, Facebox will start a second set of requests with the base URL set to /myaction/create. A fix is to redirect to a URL which handles get requests after doing a post, so you don't end up performing the post twice. Thanks very much for your help.