populating forms in jsp

[Stu Johns]

Hi I have a struts action which sets a value on an DynaActionForm

   DynaActionForm dForm = (DynaActionForm)form;
long a = 9998L;
dForm.set("sid", a);

When I try and use these on the jsp with the struts taglibrary with this form i can use the value i set, (great).

  <html:hidden property="sid"/>  

However when I try and use with EL it does not work (not great!):

  <input type="hidden" name="sid" value="${param.sid}" />  

Does anyone know why? i thought form data was just parameters on the request, is it because parameters are supposed to be read only in which case modifying them is bad?.

thanks.

[David Newton]

Are you loading the page with a URL parameter?

[Stu Johns]

just using the struts config to do it

 <forward name="success" path="/app/test.jsp" />   

and in the servlet

  mapping.findForward("success");   

[David Newton]

JSTL's ${param.xxx} notation is looking for a request parameter. If there's no request parameters then there's nothing for JSTL to find. ActionForm properties are not the same as request parameters: request parameters go from the client to the server, not the other way around.

[Stu Johns]

ok thanks,
I shall just add a request parameter with the value i want and use that on the jsp instead.
Stu,