Session Variables Object Lost On Redirect

[Frinavale]

I currently have a website that collects information (mainly text and integers) inputed by users and stores that information into an object which is in turn stored in Session. Each page has its own object and each object knows if it is valid or not.

Everytime the user advances to the next page it checks to see if all of the data collected up to this point is valid by checking the objects which are stored in Session.

If the object is missing or if the data is invalid the user is redirected back to the page where the error was made.

Now here's the problem....when I redirect them back to the page they came from because the object contains invalid data, the object is no longer there.

I have no idea why this happens but I would like to redisplay the data on the screen (with error messages) when the user is redirected back but I cannot do this because somehow the objects no longer exist.

Has anyone got any thoughts on why this might be?

[pricejt]

Post some code, it sounds like your just not putting it into the session correctly. I have had some problems with this and found it easiest to pass my information to a page that its only purpose is to create the sessions.

Basically I don't load my sessions on the same page as my information.

Justin

[Frinavale]

I'm starting to think that the reason I lose my session variables is because when the user types in the url of the page a new session is created and so my variables are lost. I don't know if I'm correct or not, but it does seem weird that on the page that they type the objects are there, and then when they are redirected (after putting all the objects into session) the objects are lost.

Here is some snipets of my code on the page that the user is redirected to.
************************************************** *****************************************

Private Sub GetAllObjectsFromSession()
        'Getting all objects from session
        page1Info= CType(Session("page1Info"), FirstPageInfo)
        page2Info = CType(Session("page2Info"), SecondPageInfo)
        page3Info = CType(Session("page3Info"), ThirdPageInfo)
End Sub
    Private Sub GetAllObjectsFromSession()
        'Getting all objects from session
        Session("page1Info") =page1Info
        Session("page2Info") =page2Info 
        Session("page3Info") =page3Info 
End Sub
 
 
 
 
Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 
        GetAllObjectsFromSession()
        If IsPostBack Then
            'there is some code here but will be confusing so I'm not going to post it
       Else
       'clearing the errors, and filling in the information supplied earlier
                       Try
                            clearErrors()
 
                            'checking if the objects are valid and if not displaying approriate errors
                            If Not page1Info.IsValid()Then
                                displayErrors()
                            End If
                        Catch ex2 As Exception
                            page1Info= New FirstPageInfo
                            PutAllObjectsIntoSession()
                        End Try
            End If
 

[scripto]

Couple of things

1. Session variables work only when you allow cookies, so make sure accept cookies is turned on.

2. If you use Response.Redirect() in .NET, you will have problems with Session vars. Instead use either
Response.Redirsct("nextpage.aspx", false) or
Server.Transfer()

hope this helps.

[Frinavale]

Couple of things

1. Session variables work only when you allow cookies, so make sure accept cookies is turned on.

2. If you use Response.Redirect() in .NET, you will have problems with Session vars. Instead use either
Response.Redirsct("nextpage.aspx", false) or
Server.Transfer()

hope this helps.

I have tried Server.Transfer before but ran into an interesting issue and read about a few problems that happen when you have presistant data...

When I tried Server.Transfer the first page wrote to the Response buffer and then when we were directed (with server.transfer) to the second page that page's content was then appended to the first page's content. This would effectivly show 2 pages on one page.

I couldn't figure out how to flush the buffer just before the new content was written so I changed back to Response.Redirect.

I've never heard of Response.Redirsct("nextpage.aspx", false) so I will look it up and see if it helps. Thanks alot!