accessing radiobuttons

[Martien van Wanrooij]

I am working on a site with some pages that all have a form that starts with
a group of radiobuttons. By default none of the buttons is checked. Before
submitting the form there is a validation script that verifies if a choice
has been made.

The following code works, but only for one individual page
function showChecked()
{
if(!document.forms[0].heeftPartner[0].checked &&
!document.forms[0].heeftPartner[1].checked)alert ('Please answer this
question');
else document.forms[0].submit();
}

In every page there will come an almost similar script, only the number of
radiobuttons belonging to the same group varies and every group also has a
different name.
As far as I tried out, when I write document.forms[0].elements[0] the
"heeftPartner" group can also be accessed, but I didn't find a method to
acces every individual element. So I would like a script that
- chooses the first element of the first form (which is always a radio
button group)
- verifies if one of the radio buttons has been checked
If I could retrieve the number of buttons in a group by something like
forms[0].elements[0].length I could make something like

var theLength = forms[0].elements[0].length
var isAnswered = false;
for(i = 0; i < theLength; i++)
{
if (document.forms[0].element[0][i].checked) //and obviously this does
not work!!!
{
isAnswered = true;
break;
}
}
if (isAnswered) document[0].forms[0].submit();
else alert('Please answer this question');

Even if the script has to be a little bit more complicated it is still worth
the trouble because there are a lot of pages.
Thanks for any suggestions,

Martien van Wanrooij

[Michael Winter]

On Sun, 18 Jan 2004 11:56:49 +0100, Martien van Wanrooij
<in**@martienvanwanrooij.nl> wrote:

I am working on a site with some pages that all have a form that starts
with a group of radiobuttons. By default none of the buttons is
checked. Before submitting the form there is a validation script that
verifies if a choice has been made.

When you use form.elements[index], where form represents a form object and
index is a positive integer, you will obtain a reference to the control at
that index in the form. If you use form.elements['name'], where name is
the name of the control, you will obtain a collection of all controls in
that form, with that name.

That's how you can access a group of radio buttons[1].

That should help you on your way,
Mike
[1] There are other methods.

--
Michael Winter
M.******@blueyonder.co.invalid (replace ".invalid" with ".uk" to reply)

[Martien van Wanrooij]

"Michael Winter" <M.******@blueyonder.co.invalid> schreef in bericht
news:op**************@news-text.blueyonder.co.uk...

If you use form.elements['name'], where name is
the name of the control, you will obtain a collection of all controls in
that form, with that name.

Thank you, Michael, this works exactly as I wanted :)

Martien van Wanrooij

[Newsgroups]

Here's how to reference using DHTML (vice DOM)...

A set of radio buttons that work together all have the same name - so if
you reference that name you get an array of all radio buttons that have
that same name. So here is some shell code that iterates through all the
radio buttons...

<input type'radio' name='heeftPartner'
onclick='doSomething(document.formname.heeftPartne r);'
value='whatever'>whatever</input>
<!-- more radio buttons here all w/ the same name -->

<script>
function doSomething (buttonList) {
for (var i=0; i=buttonList.length; i++) {
if (buttonList[i].selected == true) {
// do something if this is selected
}
}
}
</script>

Martien van Wanrooij wrote:

"Michael Winter" <M.******@blueyonder.co.invalid> schreef in bericht
news:op**************@news-text.blueyonder.co.uk...

If you use form.elements['name'], where name is
the name of the control, you will obtain a collection of all controls in
that form, with that name.

Thank you, Michael, this works exactly as I wanted :)

Martien van Wanrooij