[whatwg] 4.10.5 - value of hidden inputs

Sun Oct 11 18:44:39 PDT 2009

On Tue, 6 Oct 2009, Kartikaya Gupta wrote:
>
> If we have this page:
> 
> <html><body>
> <input type="hidden" value="foo" id="i">
> <script type="text/javascript">
>   var i = document.getElementById('i');
>   i.value = 'bar';
>   alert( i.getAttribute('value') );
> </script>
> </body></html>
> 
> What should the alert display?

It was foo, per the spec.

> From my reading of the spec I believe it should display 'foo'. For 
> type=hidden, "The value IDL attribute applies to this element and is in 
> mode value" and in mode value, "On setting, it must set the element's 
> value to the new value, set the element's dirty value flag to true 
> [...]". Reading the content attribute after should still return the 
> original 'foo'.
> 
> However, Firefox, Opera, IE6, and Chrome all alert 'bar'.

Fixed the spec.

> If I change the type from hidden to text, then FF, Opera, and Chrome all 
> alert 'foo', but IE6 still gives me 'bar'. This, despite both 'hidden' 
> and 'text' are in mode value, and so should behave the same according to 
> the spec.

IE does all kinds of weird things with forms. Try getAttribute('defaultValue')...

> Another related test case is this one:
> 
> <html><body>
> <input type="hidden" value="foo" id="i">
> <script type="text/javascript">
>   var i = document.getElementById('i');
>   i.value = 'bar';
>   i.removeAttribute('value');
>   alert( i.value );
> </script>
> </body></html>
> 
> According to the spec, setting i.value should set the dirty value flag. 
> This means that when the content attribute is removed, it shouldn't 
> affect what i.value returns for the alert. However, Firefox, Opera, and 
> Chrome all alert the empty string. It seems they all have special 
> behavior for type=hidden that isn't specced fully.

This is now fixed too, as far as I can tell.

Thanks,
-- 
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