Selective submission of form elements

I have a form that has hidden elements in it to create a pseudo-array of comma-separated values that will be submitted to the server through post, where the hidden elements will then be decoded into arrays and processed for storage. To fill the hidden elements, I use visible elements and a button that javascript handles to add values to the hidden elements, clearing the form every time the button is pressed.

Here is the question: How do I get the visible elements NOT to be submitted to the server and only submit the hidden elements in an effort to save bandwidth? Is there a way to create a text entry field that doesn't get submitted with the rest of the form, but that javascript and normal form controls can still access? Th开发者_开发技巧e goal here is to prevent unnecessary repeats of the same data being sent when the submit button is clicked, AFTER javascript has filled the pseudo-arrays with the data I need.

EDIT: Thanks for the help. The first two answers I got were good, but I chose as an answer the one I thought was a little more detailed and helpful to myself and anyone else who may be looking for the same solutions.

PLAN: I'll have an onsubmit script that disables unneeded fields just before submit so that they don't get sent to the server, thereby saving (a tiny bit of) bandwidth and reducing the amount of information my server-side script needs to do. This keeps it possible to easily use javascript to clear the fields I want cleared while constantly keeping the hidden fields loaded with the CSV's I need.

There are two provabilities that I can think of now:

1. Put visible input elements outside form tag, leave only submit button and hidden fields inside.
2. Create an event onsubmit on form element to set disabled property on visible fields. On some browser that may require to additionally remove that event, return false and trigger form submission manually.

You can set the "disabled" property of the elements to true in order to prevent them from being submitted.