322490 - Setting self.location.href during javascript keypress event has strange behavior.

Status: UNCONFIRMED

(Core :: DOM: UI Events & Focus Handling, defect)

Description

[Kai Ruhnau]

User-Agent:       Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8) Gecko/20051205 Firefox/1.5
Build Identifier: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8) Gecko/20051205 Firefox/1.5

Please see attached file.

I have an onkeypress javascript event, that is attached to an <input type=text name=wrong> field via addEventListener. This input field waits for event.keyCode==13 to set self.location.href to a self link with a special parameter.

However, if I construct the attached special case, the form is submitted instead of getting the page set via self.location.href. That means, pressing enter on the input field submits the form.

Reproducible: Always

Steps to Reproduce:
1. Load the attached file into Firefox.
2. Press ENTER in the input field.
3. The addressline changes to something with parameters "wrong=15".
Actual Results:  
"wrong=15" means, that the form was submittet...

Expected Results:  
...instead of the self.location.href with parameter "right".

There are several circumstances wich trigger the expected ("right") behavior. These are integrated as comments into the attached file. Any change alone is sufficient.

- Adding a second <input type=text> field to the form
- changing the event attachment from addEventListener to element.onkeypress
- Adding an alert between "self.location.href=..." and "return false" (note: an alert before self.location.href only shows, that the event listener is always called as expected)

I tested this on Firefox 1.5 both Windows and Linux and Firefox 1.0.7 on Windows.

Comment 1

[Kai Ruhnau]

Attachment: testcase

Comment 2

[Martijn Wargers (dead)]

You have to use event.preventDefault(); when you use addEventListener, you can't cancel the event with return false in that case.

Comment 3

[Kai Ruhnau]

Ok.

But why does any of the mentioned changes (second input / alert box / element.onkeypress) give me the - if I understand you right - wrong behavior?

Comment 4

[Martijn Wargers (dead)]

Attachment: testcase

Interesting.
There is indeed a difference there when another form control is in the form.
Adding an alert doesn't make a difference to me.
I've removed the return false in this testcase completely, since it doesn't seem to matter in the difference of behavior.

Comment 5

[Martijn Wargers (dead)]

Ah, see:
http://bonsai.mozilla.org/cvsblame.cgi?file=mozilla/content/html/content/src/nsHTMLInputElement.cpp&rev=1.419#954
That is actually wanted behavior.
When there are more than two text controls in a form without a submit button, the form will not submit when pressing enter, that is also what IE6 does.

Comment 6

[Martijn Wargers (dead)]

So that's why adding a second input tag 'works', form submission by pressing enter is then automatically suppressed.

Comment 7

[Kai Ruhnau]

I cancel the event now to prevent automatic form submission.

But I have to say that this is not a very self-explanatory behavior. What was the background of IE to handle only-one-input-forms special? Arbitrariness? Where is it used or is this a compatibility thing that should be dropped?

Thanks for the clarification.