using xajax in button and textfield

[eluser]pandjie[/eluser]
do you mean something like this ?

Code:

function process_form($form_data){
            $objResponse = new xajaxResponse();
            $name = 'txt_value';
            $objResponse->addAssign($name, "value", "test");
            return $objResponse;
        }

and

Code:

<form name="ajaxform" id="ajaxform" onsubmit="return false;">
          This is your name :
          <input type="text" id="txt_value" name="txt_value" size="20"/>
          <input type="submit" value="submit" onclick="xajax_process_form(xajax.getFormValues('ajaxform'));"/>
  </form>

It still doesn't work. I'm confusing. Is that about xajax version ?
I use xajax0.5 beta 4b.