How to validate the input field values before leaving the JSP page?

How to validate the input field values before leaving the JSP page?

I set up a jsp page (say: first.jsp) with a couple of input-/entryfields in 
a form.
After the user entered some values he clicks on the submit button.
Normally (if all values are acceptable) the user should be forwarded to the 
next page (next.jsp).
If (and only then) the values are wrong the user should stay on the current 
page and some
error messages should appear at the top of current jsp.

Thus what I need is a code execution BEFORE leaving the current page and not
 (only) when the
page is created.

How do I implement this with JavaServerPages (under JBoss) ?
Unfortuantely there is no command like

<form action="if (validate(this.formdata)==true) next.jsp else first.jsp">

Arnold

Post Follow-up to this message

Arnold Peters
10-14-04 01:57 AM

Re: How to validate the input field values before leaving the JSP page?

On Wed, 13 Oct 2004 23:07:20 +0200, apet10@hotmail.com (Arnold Peters)
wrote:

>I set up a jsp page (say: first.jsp) with a couple of input-/entryfields in
 a form.
>After the user entered some values he clicks on the submit button.
>Normally (if all values are acceptable) the user should be forwarded to the
 next page (next.jsp).
>If (and only then) the values are wrong the user should stay on the current
 page and some
>error messages should appear at the top of current jsp.
>
>Thus what I need is a code execution BEFORE leaving the current page and no
t (only) when the
>page is created.
>
>How do I implement this with JavaServerPages (under JBoss) ?
>Unfortuantely there is no command like
>
> <form action="if (validate(this.formdata)==true) next.jsp else first.jsp">

Many ways to do it.

1) If you are certain the user won't disable javascript, you can use
that.

or

2) in your next.jsp, check the values, if bad, send it back.

Struts has this built in with its validator framework.

--
now with more cowbell

Post Follow-up to this message

Bryce
10-14-04 01:57 AM

Re: How to validate the input field values before leaving the JSP page?

Arnold:
You mixed two confs. This question is for  comp.lang.javascript
Anyway here is answer:
<html>
<form name=f onsubmit="
if (f.p.value=='1') f.action='m1.jsp';
else f.action='m2.jsp';
">
<SELECT NAME='p'>
<OPTION value=1>One
<OPTION value=2>Two
</SELECT>

<input type=submit>
</form>
</html>

Alex Kizub.
Arnold Peters wrote:

> I set up a jsp page (say: first.jsp) with a couple of input-/entryfields i
n a form.
> After the user entered some values he clicks on the submit button.
> Normally (if all values are acceptable) the user should be forwarded to th
e next page (next.jsp).
> If (and only then) the values are wrong the user should stay on the curren
t page and some
> error messages should appear at the top of current jsp.
>
> Thus what I need is a code execution BEFORE leaving the current page and n
ot (only) when the
> page is created.
>
> How do I implement this with JavaServerPages (under JBoss) ?
> Unfortuantely there is no command like
>
>  <form action="if (validate(this.formdata)==true) next.jsp else first.jsp"
>
>
> Arnold

Post Follow-up to this message

Alex Kizub
10-14-04 01:57 AM

Re: How to validate the input field values before leaving the JSP page?

this kind of work should be done at the client side
use Javascript

"Arnold Peters" <apet10@hotmail.com> 写入邮件
news:ckk5e8$dvp$03$1@news.t-online.com...
> I set up a jsp page (say: first.jsp) with a couple of input-/entryfields
in a form.
> After the user entered some values he clicks on the submit button.
> Normally (if all values are acceptable) the user should be forwarded to
the next page (next.jsp).
> If (and only then) the values are wrong the user should stay on the
current page and some
> error messages should appear at the top of current jsp.
>
> Thus what I need is a code execution BEFORE leaving the current page and
not (only) when the
> page is created.
>
> How do I implement this with JavaServerPages (under JBoss) ?
> Unfortuantely there is no command like
>
>  <form action="if (validate(this.formdata)==true) next.jsp else
first.jsp">
>
> Arnold
>

Post Follow-up to this message

Sting
10-15-04 08:56 AM

Re: How to validate the input field values before leaving the JSP page?

apet10@hotmail.com (Arnold Peters) wrote in message news:<ckk5e8$dvp$03$1@news.t-online.com
>...
> I set up a jsp page (say: first.jsp) with a couple of input-/entryfields i
n a form.
> After the user entered some values he clicks on the submit button.
> Normally (if all values are acceptable) the user should be forwarded to th
e next page (next.jsp).
> If (and only then) the values are wrong the user should stay on the curren
t page and some
> error messages should appear at the top of current jsp.
>
> Thus what I need is a code execution BEFORE leaving the current page and n
ot (only) when the
> page is created.
>
> How do I implement this with JavaServerPages (under JBoss) ?
> Unfortuantely there is no command like
>
>  <form action="if (validate(this.formdata)==true) next.jsp else first.jsp"
>
>
> Arnold

perhaps something like this

<form onSubmit="return somevalidation(this)">

Post Follow-up to this message

Tomer Ben-David
10-27-04 08:58 AM