Many thanks to Jim Preston!
Tom
>From: Jim Preston <[EMAIL PROTECTED]>
>Reply-To: A mailing list about Java Server Pages specification and
> reference <[EMAIL PROTECTED]>
>To: [EMAIL PROTECTED]
>Subject: Re: How can I pass an argument from a JavaScript function to a
> Jsp file?
>Date: Fri, 4 Aug 2000 14:48:55 -0700
>
>"Tonight on 'It's the Mind', we examine the phenomenon of Deja Vu . . ."
>
>Again, Java and JavaScript live in different worlds. Not only that, but
>when
>the Java in the JSP is executed, the JavaScript doesn't even exist. So
>getting JavaScript data and variables into the Java just isn't possible,
>period.
>
>So for your first example, you can certainly use the URL of a JSP there
>(I'm
>assuming that assigning to window.location causes the browser to go to that
>URL). In order for the invoked JSP to "see" your JavaScript variable, you
>would have to pass it as a parameter to the JSP, which means that the
>variable must be a simple string (or resolve to a meaningful string). For
>example, you could certainly do this:
>
>function(file_obj) {
> Window.location="MyFile.jsp?fileparm=" + file_obj;
>}
>
>if the "file_obj" thing is a file NAME rather than a full-blown object that
>you want your JSP to be able to deal with directly. This works because it's
>all in the JavaScript space, it's just invoking a URL that happens to be a
>JSP (and constructing the URL using a JavaScript variable).
>
>On the other hand, if file_obj is a JavaScript object, and you want the
>invoked JSP to have access to the object itself, I don't think you can do
>that. JavaScript objects are in a completely different space (i.e. on the
>browser) than Java (i.e. on the server) and I know of no way to pass an
>object from the former into the latter.
>
>Your second example will just not work. The JSP scriptlet:
>
><% cb.setFile(file_obj); %>
>
>Is executed on the server at page request time. The "file_obj" variable is
>in JavaScript, which doesn't even exist at that time. At page request time,
>the JavaScript is just a bunch of character data that the JSP is going to
>send to the browser. Only when it gets to the browser does it become a
>JavaScript program.
>
>You last example lives entirely in the JSP world. To pass objects (like
>Files) between JSPs, you need to store the object in the session scope so
>that the other JSP can retrieve it. Get a good book on JSP and read about
>session scope.
>
>--Jim Preston
>
>
>-----Original Message-----
>From: A mailing list about Java Server Pages specification and reference
>[mailto:[EMAIL PROTECTED]]On Behalf Of Tom Yang
>Sent: Friday, August 04, 2000 11:30 AM
>To: [EMAIL PROTECTED]
>Subject: How can I pass an argument from a JacaScript function to a Jsp
>file?
>
>
>Hi all:
> Can anyone please tell me that how I can invoke a Jsp file within the
>body
>of a JavaScript function AND pass an argument to the Jsp file? such as
>
>function(file_obj) {
> Window.location="MyFile.jsp";
>}
>
>I would like the MyFile.jsp to see the variable file_obj, and use it. But I
>don't know how to make this happen.
>
>Actually, I have two other related questions
>Firstly, can I execute a Jsp statement within the body of a JavaScript
>function? such as
>
>function(file_obj) {
> <% cb.setFile(file_obj); %>
>}
>
>I tried it. The compiler doesn't like it. Is there a way to do it? I really
>need that functionality in my programming.
>
>Secondly, oftentimes I need to invoke a Jsp page and pass an argument to
>it,
>such as in the following HTML statement
>
><A HREF="MyFile.jsp">Click Me</A>
>When I invoke that MyFile.jsp, I would like it to have an argument
>file_obj,
>which is a Jsp variable <% File file_obj; %> defined and initialized
>earlier
>in the same Jsp page.
> Your help is appreciated. Thanks!
>
>Tom
>
>
>
>
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>===========================================================================
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>Some relevant FAQs on JSP/Servlets can be found at:
>
> http://java.sun.com/products/jsp/faq.html
> http://www.esperanto.org.nz/jsp/jspfaq.html
> http://www.jguru.com/jguru/faq/faqpage.jsp?name=JSP
> http://www.jguru.com/jguru/faq/faqpage.jsp?name=Servlets
>
>===========================================================================
>To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff
>JSP-INTEREST".
>Some relevant FAQs on JSP/Servlets can be found at:
>
> http://java.sun.com/products/jsp/faq.html
> http://www.esperanto.org.nz/jsp/jspfaq.html
> http://www.jguru.com/jguru/faq/faqpage.jsp?name=JSP
> http://www.jguru.com/jguru/faq/faqpage.jsp?name=Servlets
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com
===========================================================================
To unsubscribe: mailto [EMAIL PROTECTED] with body: "signoff JSP-INTEREST".
Some relevant FAQs on JSP/Servlets can be found at:
http://java.sun.com/products/jsp/faq.html
http://www.esperanto.org.nz/jsp/jspfaq.html
http://www.jguru.com/jguru/faq/faqpage.jsp?name=JSP
http://www.jguru.com/jguru/faq/faqpage.jsp?name=Servlets
