Question

JSTL <c:if>

Asked by: jaggernat

hi experts

I have this code in my jsp page

<c:set var="screenqq" value="JWS1001"/>
      
<c:if test='${requestScope.screenqq == "JWS1001"}'>
     <c:set var="makeurl" value="option=reports"/>
</c:if>
   

<html:form action="/shopping/cart/add.do?<c:out value="${makeurl}"/>"  method="post">

when page loads ,For some reason , it says “makeurl” is empty.

Any ideas?

Thanks
J

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Asked On
2006-09-19 at 07:24:45ID21994759
Tags

jstl

Topics

Java Server Pages (JSP)

,

Java Standard Tag Library (JSTL) & Server Tags

Participating Experts
4
Points
500
Comments
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Answers

 

by: rowdy_hPosted on 2006-09-19 at 09:30:24ID: 17553402

I think your problem is that are you doing <c:if test='${requestScope.screenqq == "JWS1001"}'>
and not <c:if test='${screenqq == "JWS1001"}'>?

When you set the screenqq var you aren't specifying the scope on it. If I remember correctly the default scope is page, so you won't find it in the request scope.

 

by: jaggernatPosted on 2006-09-19 at 10:47:45ID: 17554000

used this  <c:if test='${screenqq == "JWS1001"}'>

still no luck

i think the problem is somethng else

J

 

by: jaggernatPosted on 2006-09-19 at 11:22:52ID: 17554352

Looks like i am getting close

<c:if test='${screenqq == "JWS1001"}'>
     <c:set var="makeurl" value="option=reports"/>
</c:if>
   

<c:out value='${makeurl}'/>

<html:form action="/shopping/cart/add.do?<c:out value="${makeurl}"/>"    method="post">

the above code prints "option=reports" on screen which is c:out value

but the same c:out is not working in   <html:form action="/shopping/cart/add.do?<c:out value="${makeurl}"/>"    method="post">


ideas?

J

 

by: rowdy_hPosted on 2006-09-19 at 13:45:54ID: 17555633

I know I have had some difficulty with interaction between html tags and c tags.
What does the page source show?

Alternatives are to use scriptlets instead of the c tags, or just to write out the form in normal html instead of with the html taglib
(i.e. <form action="/shopping/cart/add.do?<c:out value="${makeurl}"/>"    method="post">) of course you then have to make sure all the form elements you use are written out normally instead of using the html taglib.

 

by: jaggernatPosted on 2006-09-19 at 14:31:45ID: 17555947

oh boy.this really is frustrating, i am trying to get it run since morning!
<html:form...> with <c:  tag    just  doesnt work.

i dont think i can avoid html taglib in my jsp.

anyway , thanks for help
If you find anything let me know
J

 

by: boonlengPosted on 2006-09-19 at 22:54:31ID: 17558324

Since it a form post, may be you can change it to hidden field instead of parameter.
Example:

<html:form action="/shopping/cart/add.do" method="post">
<c:if test='${screenqq == "JWS1001"}'>
     <input type="hidden" name="option" value="reports">
</c:if>


Regards,
Boon Leng

 

by: jaggernatPosted on 2006-09-20 at 05:52:08ID: 17560227

ok, and then how do i append it to the URL. I want to add "option=reports" to the url ="/shopping/cart/add.do"  something like
this
<html:form action="/shopping/cart/add.do?option=reports" method="post">

similarly , if someother <c:if> condition is true, i want

<html:form action="/shopping/cart/add.do?option=myCart" method="post">


Is that possible?
J

 

by: reach2piyushPosted on 2006-09-20 at 23:01:46ID: 17566840

This may be a problem with quotes, try
<html:form action='/shopping/cart/add.do?<c:out value="${makeurl}"/>'    method="post">

also you can try the following:
<c:choose>
      <c:when test='${screenqq == "JWS1001"}' >
                     <html:form action="/shopping/cart/add.do?option=myCart" method="post">
      </c:when>
      <c:otherwise>
                       <html:form action="/shopping/cart/add.do?option=reports" method="post">
      </c:otherwise>
</c:choose>

 

by: jaggernatPosted on 2006-09-21 at 06:11:13ID: 17568712

>>>>>>>>>>>
<c:choose>
     <c:when test='${screenqq == "JWS1001"}' >
                     <html:form action="/shopping/cart/add.do?option=myCart" method="post">
     </c:when>
     <c:otherwise>
                       <html:form action="/shopping/cart/add.do?option=reports" method="post">
     </c:otherwise>
</c:choose>


are you sure the above works on your system. I doesnt work on mine.


J

 

by: jaggernatPosted on 2006-09-21 at 06:46:12ID: 17569024

and neither does

<html:form action='/shopping/cart/add.do?<c:out value="${makeurl}"/>'    method="post">

can you please let me know if it works on your system.

thanks
J

 

by: ss_pPosted on 2006-09-21 at 07:51:29ID: 17569694

hi

can you check which JSTL version are you using

see the tag lib definition

<%@ taglib uri="http://java.sun.com/jstl/core" prefix="c" %>
to
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

which one have you used

 

by: jaggernatPosted on 2006-09-21 at 10:36:47ID: 17571374

 

by: ss_pPosted on 2006-09-21 at 12:09:51ID: 17572116

in that case

try this one

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

 

by: jaggernatPosted on 2006-09-21 at 13:08:02ID: 17572533

<c:choose>
     <c:when test='${screenqq == "JWS1001"}' >
                     <html:form action="/shopping/cart/add.do?option=myCart" method="post">
     </c:when>
     <c:otherwise>
                       <html:form action="/shopping/cart/add.do?option=reports" method="post">
     </c:otherwise>
</c:choose>


will something like above work with <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

 

by: reach2piyushPosted on 2006-09-21 at 18:39:18ID: 17574552

I am using JSTL 1.0 in our application so the taglib def looks like
<%@ taglib prefix="c" uri="http://java.sun.com/jstl/core" %>

I am not sure what you wanted me to confirm working on my system,
 choose-when-otherwise construct is working at all places in my code
 I am not using html taglib in my code, so cannot confirm on the combination,  

For generating dynamic URL, most of the time I code my logic in the controller & put the URL as an attribute in the request & in most of my JSPs, form definition looks like the following & this surely works:
<form method="post" action="<c:out value='${nextUrl}' />" name="thisDocForm">

 

by: jaggernatPosted on 2006-09-21 at 19:57:30ID: 17574872

>>>I am not sure what you wanted me to confirm working on my system

I wanted you to confirm if something like this works on your system:
<html:form action="<c:out value='${nextUrl}' />"    method="post">

most probably it will not, because <html: > tags do not seem to work with <c:> tags.



 

by: reach2piyushPosted on 2006-09-22 at 02:21:11ID: 17576268

oh, I misunderstood your problem,  your problem is to use JSTL along with Struts tags,  & yes you are correct this will not work with regular Struts tags..

To use Expression language syntax through struts tag libraries (1.2.8 onwards or just include struts-el.jar & TLD file from it), & in your code
<%@ taglib uri="/WEB-INF/lib/struts-html-el.tld" prefix="html-el" %>
<html-el:form action="${nextUrl}"    method="post">

 

by: jaggernatPosted on 2006-09-22 at 06:52:55ID: 17577545

thats kool.
we are still using struts 1.1.

do you know how and from  where i can upgrade to 1.2.8 and then eventually download struts-html-el.tld.


thanks for the info
J

 

by: ss_pPosted on 2006-09-22 at 06:55:14ID: 17577561

you can download it from

http://struts.apache.org/

 

by: jaggernatPosted on 2006-09-22 at 07:17:14ID: 17577718

i downloaded

struts-1.2.8-lib

but i dont see any   struts-el.jar


thanks
J

 

by: ss_pPosted on 2006-09-22 at 07:23:49ID: 17577765

struts-el.jar is already included in struts.jar

you can find struts-el.jar in struts.jar

download struts 1.2.8 u can find struts-el.jar is already included in struts.jar

 

by: jaggernatPosted on 2006-09-22 at 07:32:14ID: 17577828

oh ok. thanks

will something like this work

<c:set var="makeurl" value="method=save"/>
<html-el:form action="/casemngt/OrderInfo1.do?${makeurl}"    method="post">

thanks
J

 

by: jaggernatPosted on 2006-09-22 at 08:05:33ID: 17578096

Niceeeeee.
It does work.

thanks guys, I really appreciate it.

J

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