Setting forms using Javascript

[daniel kaplan]

Hi All,

Been learning Javascript (via google) to create forms with pre-set values.
As seen below. My problem I have found is this: I can't seem to figure out
(or find so far via google) how to preset form options when the input type
is a radio button, or dropdown list. The same method does not seem to work
with input fields.

Anyone know of such a comprehensive site?

Thanks ahead,

Daniel

<FORM name="PersProf" action="newuser.pl" method="POST">

<table border="0">
<tr>
<td WIDTH="200">
First Name
</td>
<td>
<input type="text" name="first_name" maxlength=32 size = 32>
</td>
</tr>
</table>
<script language="JavaScript">
<!--
//setting the value:
document.PersProf.first_name.value = '$first_name';
-->
</script>

[Ulrik Skovenborg]

daniel kaplan wrote:

My problem I have found is this: I can't seem to figure out
(or find so far via google) how to preset form options when the input type
is a radio button, or dropdown list. The same method does not seem to work
with input fields.

Do you mean preselected:
<input type="radio" checked> and
<option selected value="val">text</option>

[Michael Winter]

On Sat, 11 Dec 2004 09:45:59 -0500, daniel kaplan <no****@nospam.com>
wrote:

Hi All,

Been learning Javascript (via google) to create forms
with pre-set values.
You don't specify initial values with Javascript. You specify them in HTML:

<input type="text" ... value="initial value">

<input type="checkbox" ... checked>

<input type="radio" ... checked>

<select ...>
<option ... selected>...</option>
</select>

<textarea ...>initial value</textarea>

I suggest you read the HTML Specification
(<URL:http://www.w3.org/TR/html4/>), rather than rely on the Web.
Information regarding forms can be found under section 17
(<URL:http://www.w3.org/TR/html4/interact/forms.html>).

If you have any further problems, please ask in alt.html or
comp.infosystems.www.authoring.html.

[snip]
<script language="JavaScript">
The language attribute has been deprecated for over six years. Use the
type attribute instead:

<script type="text/javascript">
<!--
Hiding scripts with SGML comment delimiters is an obsolete practice. It's
not necessary.
//setting the value:
document.PersProf.first_name.value = '$first_name';

The preferred way to access form controls is via the forms and elements
collections:

document.forms['form-id'].elements['control-name-or-id']

[snip]

Good luck,
Mike

--
Michael Winter
Replace ".invalid" with ".uk" to reply by e-mail.

[daniel kaplan]

"Michael Winter" <M.******@blueyonder.co.invalid> wrote in message
news:opsium76g8x13kvk@atlantis...

You don't specify initial values with Javascript. You specify them in

HTML:

i guess since i was able to set the initial value of a TEXT field using
javascript, that i could do the same with ALL fields in the form...

and i using perl to generate the HTML dynamically, so my perl build the
html, with javascript included...

i can set them using HTML, but to do it dynamcially i turned to java....

strange that it allows me to do it for text and nothing else, no?

daniel

[Ivo]

"daniel kaplan" wrote

i guess since i was able to set the initial value of a TEXT field using
javascript, that i could do the same with ALL fields in the form...
Being able to do something is never a good reason to go do it. In
programming the question should be: is it necessary? Here the answer is a
crystal clear no, see below.
and i using perl to generate the HTML dynamically, so my perl build the
html, with javascript included...

i can set them using HTML, but to do it dynamcially i turned to java....
Java? I didn't see any java in your earlier code. It 's javascript, a
totally different and independent language. The names are confusing,
no one disagrees with that, but the environments in which they operate,
are incomparable, even within the same webbrowser.
strange that it allows me to do it for text and nothing else, no?

It does allow you to do it for all types of input elements. The point is
that you don't need javascript at all. Let your perl script write the values
directly in the value attributes of the elements. From your first post I
gather that in the perl syntax it would look like this:

<input type="text" name="first_name" value="$first_name">

Look Ma, no javascript!
--
Ivo
http://www.vansandick.com/

[daniel kaplan]

"Ivo" <[e-mail]> wrote in message
news:41**********************@news.wanadoo.nl...

Being able to do something is never a good reason to go do it. well, it seemed that javascript was rich Forms features. of course am
totally new to it, so that is how it appears to me, it coudl be wrong

Java? I didn't see any java in your earlier code. obviously i typo'ed there
It does allow you to do it for all types of input elements. do you know a decent website which points this out? even if i don't end up
using that part of it, i would still like to learn it.

The point is that you don't need javascript at all. Let your perl script write the values directly in the value attributes of the elements. From your first post I
gather that in the perl syntax it would look like this:

<input type="text" name="first_name" value="$first_name">

that is how i started...but when it came to other forms features such as a
drop down list of states, where one might already be sleceted, it obviously
was going to be much more coding. i.e. (OPTION vs. SELECTED) so that's why
i turned to look at javascript.

thanks,

daniel

[Randy Webb]

daniel kaplan wrote:

"Ivo" <[e-mail]> wrote in message
news:41**********************@news.wanadoo.nl...

The point is that you don't need javascript at all. Let your perl script
write the values directly in the value attributes of the elements. From
your first post I gather that in the perl syntax it would look like this:

<input type="text" name="first_name" value="$first_name">

that is how i started...but when it came to other forms features such as a
drop down list of states, where one might already be sleceted, it obviously
was going to be much more coding. i.e. (OPTION vs. SELECTED) so that's why
i turned to look at javascript.

Hava Perl generate the select element. As it loops through the elements
of an array to create it, have it check the value, if they match, then
add the selected.

--
Randy
comp.lang.javascript FAQ - http://jibbering.com/faq

[daniel kaplan]

"Randy Webb" <Hi************@aol.com> wrote in message
news:vM********************@comcast.com...

Hava Perl generate the select element. As it loops through the elements
of an array to create it, have it check the value, if they match, then
add the selected.

well i am doing that with a lot of Ternery statements, because i am using
perl to build out the entire HTML page...it's just messy, so i assumed that
using javascript to do it at the end would have been cleaner

[Ivo]

"Randy Webb" wrote

daniel kaplan wrote:"

"Ivo" <[e-mail]> wrote

Being able to do something is never a good reason to go do it. well, it seemed that javascript was rich Forms features. of course am
totally new to it, so that is how it appears to me, it coudl be wrong

The rule applies to all things. As far as javascript is concerned, you 'll
stop being new after reading the FAQ of this newsgroup
http://www.jibbering.com/faq/

and related documents, and you understand why the sport is to rely on
javascript as little as possible. You control what happens on the server,
but when a page reaches the client, you just don't know what browser on what
OS is claiming to be some other browser, scripts may even be rewritten by
proxies and plugins (think popup blockers) and by the user himself. Most
importantly, a lot of people surf with javascript disabled or simply not
available, by choice or otherwise (estimates vary between 5%-25%). So you
want your page to be complete when you send it, and use javascript only for
things that are impossible without javascript.
Hava Perl generate the select element. As it loops through the elements
of an array to create it, have it check the value, if they match, then
add the selected.

Here is how I do them in PHP:

<?
function writeselect($name,$atb='',$ops=array(),$sel=''){
$s='<select name="'.$name.'" id="'.$name.'" '.$atb.'>';
$t=0; foreach($ops as $n=>$v) { $s.='<option
value="'.($t===$n?$v:$n).'"'.(($v==$sel)?' selected':'').'>'.$v; $t++;}
return $s.'</select>';
}
?>
<label for="cat" title="Grouping by topic">Category: </label>
<?=writeselect('cat','class="put"',array('Art', 'Business',
'Computing', 'General', 'Travel'),'General');?>
<?=writeselect('amount','onchange="foo(this);"',ar ray('Amount', 1=>'One',
12=>'Dozen'));?>

--
Ivo
http://4umi.com/web/javascript/

[Randy Webb]

daniel kaplan wrote:

"Randy Webb" <Hi************@aol.com> wrote in message
news:vM********************@comcast.com...

Hava Perl generate the select element. As it loops through the elements
of an array to create it, have it check the value, if they match, then
add the selected.

well i am doing that with a lot of Ternery statements, because i am using
perl to build out the entire HTML page...it's just messy, so i assumed that
using javascript to do it at the end would have been cleaner

As Ivo has said, never rely on JS. Use it as an addition but never a
requirement.

--
Randy
comp.lang.javascript FAQ - http://jibbering.com/faq

[daniel kaplan]

"Randy Webb" <Hi************@aol.com> wrote in message
news:Ac********************@comcast.com...

daniel kaplan wrote: As Ivo has said, never rely on JS. Use it as an addition but never a
requirement.

thanks all for the advice...

daniel

[Dr John Stockton]

JRS: In article <11***************@nntp.acecape.com>, dated Sat, 11 Dec
2004 14:18:40, seen in news:comp.lang.javascript, daniel kaplan
<no****@nospam.com> posted :

"Michael Winter" <M.******@blueyonder.co.invalid> wrote in message
news:opsium76g8x13kvk@atlantis...

You don't specify initial values with Javascript. You specify them in

HTML:

i guess since i was able to set the initial value of a TEXT field using
javascript, that i could do the same with ALL fields in the form...

You cannot set the initial value of an HTML text field with javascript;
you can only replace it - before the user notices!

The same goes for other controls.

AFAIK, in javascript you can re-set the value of any identifiable
control that exists. Even an isolated radio-button can, ISTM, be cleared
by code.
// // // document.write("<input type=radio name=X> Do Not Touch") // !!

In javascript, you can output HTML, including creation of controls with
computed initial values; but that is not quite the same thing.

--
© John Stockton, Surrey, UK. ?@merlyn.demon.co.uk Turnpike v4.00 IE 4 ©
<URL:http://www.jibbering.com/faq/> JL/RC: FAQ of news:comp.lang.javascript
<URL:http://www.merlyn.demon.co.uk/js-index.htm> jscr maths, dates, sources.
<URL:http://www.merlyn.demon.co.uk/> TP/BP/Delphi/jscr/&c, FAQ items, links.

[David Dorward]

daniel kaplan wrote:

well i am doing that with a lot of Ternery statements, because i am using
perl to build out the entire HTML page...it's just messy

Try installing Template::Toolkit, it makes things rather cleaner.

In the Perl you would build a data structure (possibly from a database) that
looks something like:

$myHashRef = {
selectItems => {
one => {
value => 1,
label => 'Thingy',
},
two => {
value => 'wibble',
label => 'Wibble',
},
foo => {
value => 3,
label => 'Baz',
select => 1,
},
},
};

and include something like this in the template:

<select name="mySelect">
[% foreach item = selectItems %]
<option value="[% item.value %]"[% IF item.select %] selected[% END %]>
[% item.label %]
</option>
[% END %]
</select>

--
David Dorward <http://blog.dorward.me.uk/> <http://dorward.me.uk/>
Home is where the ~/.bashrc is