Struts and ajax for input validation check

Question

Hi there
I am not quite sure where I should post this question. I have a question about using ajax to check input valudation check on a jsp page which uses struts tab libs.
For example, I want to check if input email has already existed in the database on the sign up page. If it is, a sameEmail jsp page will through out in the span area. Meanwhile, the form on this page should not be allowed to submit.
Email test field
<div><html:text property="email" onkeyup="showHint(this.value, 'hint', 'errors/sameEmail.jsp')"/><span id="hint"></span></div>There are two strateies in my mind
Strategy 1. Disable the submit button when sameEmail.jsp is throwed out.
I named all buttons operation in sign up page, so LookupDispatchAction page can process all the logical work depends on the value of these buttons. My questions is how I can disable signup submit button in javascript, as I need use this element id or name? Apperantly, I cannot add id into Strut 2 jsp page, plugs all buttons' names are the same on the sign up page.
For example:
     <html:submit property="operation">
          <bean:message key="adminMainForm.signUpButtonLabel"/>
     </html:submit>
<html:submit property="operation">
     <bean:message key="adminMainForm.deleteAll" />
     </html:submit> Strategy 2. Write something in the js page, which will block the data transfer.
Something similar to
function validateSignupInput(form) {
if(form.customerEmail.value.exist()){
return false;
} Appearntly it doesn't work.
My question is that how I can write this piece of js code.
Any idea will be helpful, thank you.
Ming

Answer 1

Hi Karan,
I did not get ur requirement but if the question deals with selection screens, I have an answer for it.
before u do all these things, first you need to trigger an event called AT SELECTION-SCREEN.
example code is :
AT SELECTION-SCREEN.
    IF (fld name) > (value)   -
> any logic which u need
           message
   endif.