Quoting Seth Freach <[email protected]>:
Earnie,
If you have a simple form as follows:
<form>
<input type="text" id="alpha" class="check-on-change" />
<input type="text" id="beta" class="check-on-change" />
<input type="text" id="gamma" />
</form>
to do a simple auto population of the third field based on the sum
of the first two with jquery would look like this:
<javascript>
$(document).ready(function() {
$('.check-on-change').change(show_sum);
});
function show_sum() {
var a = $('#alpha").val();
var b = $('#beta").val();
$('#gamma').val(a + b);
}
</javascript>
In jQuery, you access DOM elements with "selectors", which are
strings that follow the exact same syntax as CSS, but wrapped in
"$(...)". Once you have accessed them like this, you can perform
functions on them such as .val() with no params to /get/ the current
form field value, or val(x) with a parameter to /set/ the value.
the first bit, "$(document).ready(function(){...});, set's
everything up to work after the DOM has been loaded.
see http://docs.jquery.com/Core, and in particular the section on
the left of that page titled "API Reference" for lots more info.
Thanks, Seth. You've got me started and I'm thinking I need to also
add ['#ahah'] to my forms. I'm still confused by the various API but
I'll muddle through it now.
--
Earnie
-- http://r-feed.com/ -- http://for-my-kids.com/
-- http://www.4offer.biz/ -- http://give-me-an-offer.com/
