How to bind to the submit event when HTML5 validation is used?

Question

Using HTML5 validation...

In HTML5 browsers, validation occurs before the submit event. So if the form is invalid, the submit event never fires.

I would like to hook an event into the form submit, to fire whether the form validates or not. Here's a small example, where I'm trying to alert() when the user submits the form.

HTML:

<!DOCTYPE html>
<html>
    <head><title>Example</title></head>
    <body>
        <form>
            <input type="text" name="foo" required title="Foo field"/>
            <input type="submit"/>
        </form>
    </body>
</html>

JavaScript:

$(function() {
    $('form').submit(function() {
        alert('submit!')
    });
});

Interactive demo: http://jsfiddle.net/gCBbR/

My question is: do browsers provide an alternative event that I can bind to that will run before the validation?

Mohsen · Accepted Answer · 2011-09-28T22:59:57.713

Yes, there is an event for that reason. The event is called invalid when user tries to submit the for orr when you check validity via HTML5 validation method checkValidity(). This event does not fire on blur or something like that without calling checkValidity() just because you have HTML validation attributes in your input tags. But it does fire on before form submit.

From W3C:

When the checkValidity() method is invoked, if the element is a candidate for constraint validation and does not satisfy its constraints, the user agent must fire a simple event named invalid that is cancelable (but in this case has no default action) at the element and return false. Otherwise, it must only return true without doing anything else.

For example you have this markup:

<form>
            <input type="text" name="foo" required title="Foo field"/>
            <input type="submit"/>
</form>

Then you need to call checkValidity() to fire invalid event if the input data is invalid:

document.querySelectorAll('input')[0].addEventListener('blur', function(){
        this.checkValidity();
    }, false);

document.querySelectorAll('input')[0].addEventListener('invalid', function(){
        console.log('invalid fired');
    }, false);

Look at my example here: http://jsbin.com/eluwir/2

Actually this not totally true. The invalid event is fired with programmatic constraint validation (checkValidity) *and* interactive form validation (user trys to submit a form with invalid inputs). Additionally there is 2 other big differences, the invalid is fired for each invalid input and submit only once + the invalid event does not bubble to the form (you can use capture...). — alexander farkas, Sep 28 '11 at 22:28
@alexanderfarkas, you are totally right. I misunderstood the specification. Edited my answer. This event fires on before submit here: http://jsbin.com/eluwir/3/edit — Mohsen, Sep 28 '11 at 23:00

score -1 · Answer 2 · answered Oct 30 '12 at 08:47

-1

if you want to use the browser default validation you should use the following as you need to bind to the default submit then prevent the it and use $.ajax or $.post

$("form").bind('submit', function(e){
       e.preventDefault();

        $.post("url",$("form").serialize(),function(data){
                             $("#result").html(data).show();
                              });
       });

answered Oct 30 '12 at 08:47

Bakly

640
6
18

Your solution gave me a great idea to separate concerns between onClick (button) and onSubmit (form) . Thanks! – julianm Apr 13 '20 at 02:53

bazilio · Answer 3 · 2011-09-28T18:23:49.447

-1

$(function() {
    $('form').one('submit',function() {
        alert(1);

        [...]

        $(this).submit(); // optional
        return false; // returning false skips validator's trigger
    });
});

this code will be executed only once, for permanent handling use $.bind

edited Sep 28 '11 at 18:23

answered Sep 28 '11 at 18:15

bazilio

29
3

I think you mis-understood the question. The submit event is never fired if the form fails HTML5 validation. – Portman Sep 28 '11 at 18:29

How to bind to the submit event when HTML5 validation is used?

3 Answers3

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