Also please bear this in mind that the 2 classes  have no relation in via inheritance.

The .net Framework is written in C# and all the Framework objects  talk to each other. How specifically do you want them to communicate?

Infact I have 2 different pages. Now when say page 1 loads I create an object  of say Class X in the code behind. If the user clicks a hyperlink on Page1 then the Page 2 loads and the Class Y constructor (in the code behind of Page 2) is called. I wish I could pass the Class X object or its reference (not sure if we can do that in managed C#) in the Class Y constructor so that I could still use the Class X object. Do you think we can do this? If yes, then how to overload the call.

Otherwise can I use the Class X object in Class Y. I can't see it the browser object perhaps because it goes out of scope when page 1 unloads.

Just use a session to pass the object.

Discard the session var at end of second receiving page.

I will surely try that. But isn't there any better way of doing
it by the principles of OO.

A session is an object  designed to transfer objects  between stateless HTTP requests. Winforms apps or console apps are NOT stateless so it is done naturally there.

HTTP is stateless as a protocol. As long as it is, the ASP.net team can never provide a way better than this.

You can make your second class persistable, either in a session or in the database.

I have been trying to implement what you had said. Perhaps read somewhere that should avoid storing objects  in Sessions. But even having lots of problems


I have enabled sessions in both the ASP.NET pages as below:
<%@ Page language="c#" Codebehind="Categories.aspx.cs" AutoEventWireup="false" Inherits="produits_new.Categories" smartNavigation="False" enableSessionState="True" enableViewStateMac="True"%>
And I am able to store the object  in the Session in a xxx.cs file and access it later in another yyy.cs file but when the user clicks a hyperlink to open up another page I can not retrieve the session object in its code behind class. I added a watch on the session object, it says "an Exception of type System.Web.HttpException occured".

However the final error I get is "Session state can only be used when enableSessionState is set to true, either in a configuration file or in the Page directive".


Do you have any idea as to why this is happening? I am already having a tough time ....:)

Delete EnableSessionState attribute in the @Page directive and make sure it's enabled in web.config, so Session will work in all pages. Then make sure that the new window you open is opened with window.open javascript function and not via A tag like: <a href="whatever_page.aspx" TARGET="_blank"> this way the other window will reside in a different session and it won't work. At least that's the way I think it is.

And of course, make sure both pages are part of the same application. Applications don't share Session object  collection...

You are right. I replaced href using javascript function window.open and I could get back the session objects. But now without the hrefs I cannot display the links as its a menu page. Do you have any workarounds for this?

I don't think I get your problem now? Where do the hrefs get displayed? On window status bar. no problem. make an onmouseover event for A tag and set it as:
<A HREF="javascript:window.open(...);" onMouseOver="window.status='real link name';">

but you could also make it like this:

<A HREF="real_page.aspx" onClick="javascript: window.open(...); window.event.returnValue=false;">

As I was not able to access the Session object  and you told me thats bcoz of the hrefs which open the window in a different session, I have replaced all the hrefs with winow.open - javascript function. It means :

I replaced:
"<li>Continents</li>

with:
<li>Continents</li>

After that I was able to access my session object. But now my problem is that the "Continents" word on the page doesn't appear as a link.. Is there any work around for this so as to get "Continents" link and keep the same session.

You could probably use a LinkButton and add the onclick to the attributes.

<script>
function openwin(myurl)
{
winow.open(myurl,.................)
}
</script>
<a href="page.aspx" target=new>Page</a>
change to
<a href="javascript:void(0)" onclick=openwin("page.aspx")>Page</a>

This is much easier and more robust if you
use LinkButtons, as Rion suggested.
You can add an attribute to the LinkButton
in your Page_Load or some other initialization
method:

LinkButton.Attributes.Add("onclick", "javascript:window.open('" + "continents.aspx" + "'," +"'linkwindow', 'width=405,height=465')");

Well if you would read carefully, you'd see I included onClick event to the A tag, AS WELL as the HREF attribute. This way, you keep the link and make your own click "adventure"... I'm copiing the part of the code again:

<A
    HREF="other_info/continents.aspx"
    onClick="javascript: window.open('other_info/continents.aspx'); window.event.returnValue=false;">
Continents</A>

because that would cause the server event to fire instead of the client
one...

not if you get rid of the eventhandler !

//this.LinkButton1.Click += new System.EventHandler(this.LinkButton1_Click);

woops - my mistake - course it postsback

soz ... I'll think before scribbling next time.

I have done exactly as you have said. But the very inclusion of HREF tag, is creating problems as I cann't access my session object.

ok. But I tend to be "economical" don't waste resources just because I can...
It's better to use A tag, because it's much more uncomplicated object  ober
LinkButton... Anyway. YOu could use either. You could also add onclick attribute
to the linkbutton as someone suggested earlier.

There are many ways to reach your goal, you choolse the one that most suits
you...

Ok. Now I think it's time for you to explain where and what you meant with "link is not displayed"? Is that the problem of the status bar or what. To find a suitable solution to your problem... I use this exact functionality on a project I+m currently working on. First window opens and sets a Session object  and opens a child window that checks for that session. Had no problems with it...

Unfortunately, I am trying to do exactly the same as what you have been doing but I lose my session object. There is nothing happening at the status bar. But I was just going through what Stephen had suggested. It works great !!!

<li>Continent</li>;

or

<li>Continent</li>

Either of these do the job without losing the session object. Many many thanks to Stephen and you and other members as well for being so patient and helpful.

Actually I prefer Roberts version with trhe status bar set to the name of the file.

Anyone ... I am absolutely positive but cannot for the life of me recreate it .... I have it in a book (somewhere) .... how to change the class of something on rollover.

That way you could use a <asp:hyperlink> with url set to nothing, onclick as below, and mimick the A rollover

HyperLink hl = new HyperLink()
hl.Attributes["onclick"] = blah blah

hl.Attributes["onmouseover"] = "this.class='rollover'";
hl.Attributes["onmouseout"] = "this.class='rollunder'";

Actually the class attribute is named in javascript as classNamenot just class. But don't even bother doing that. Just make a class for normal A and a class with :hover for mouse over event. It works much faster than interpreted javascript. I use it all the time.

I keep promising myself to remember that every time I hit the problem, but I always forget.

className