I have a form with a series of text fields.

3 of them have to be combined into a hidden field before submission.

I have found http://jsfiddle.net/Tyriar/5ERRG/ a few hours ago and I am trying to adapt it to a form.

The <div id="output"></div> would be the hidden input.

And <button id="test">Test</button> would be replaced by the submit button.

In the first place, after editing the code and changing <div id="output"></div> for <input id="output"/> the fourth field does not receive any content from the 3 fields above, so I have no tested it in a form.

Some idea on how to adapt the code to my project?

If such a thing is possible.

In other case, I would appreciate some other way to do it.

Thanks for your help.

Best regards.