Session Variable not changing

No...because sometimes the request.querystring("customer") will be nothing, and at that point, I don't want to "empty out" the session variable.  I only want to reset the variable to something different if request.querystring("customer") is found or defined.

Er, doesn't your line:
   If Request.QueryString("Customer") = "" Then
take care of that?

Think about it. What purpose does x = x serve? That's what your original code is doing.

-- Jon500

Sorry--I misread something... Give me a sec...

Here is some debugging:

Private Sub DoSessionStuffHere()

        If Request.QueryString("Customer") = "" Then
            Response.Write("<script> alert('inside session') </script>")
            Session("MyCurrentCustomer") = Session("MyCurrentCustomer")
            Response.Write("<script> alert('" + Session.Item("MyCurrentCustomer") + "') </script>")

        ElseIf Request.QueryString("Customer") <> "" Then
            'Session.Abandon()
            'Session.Clear()
            Response.Write("<script> alert('inside session 2') </script>")
            Session.Item("MyCurrentCustomer") = Request.QueryString("Customer").ToString
            Response.Write("<script> alert('2:" + Session.Item("MyCurrentCustomer") + "') </script>")
        End If

    End Sub

If you look at the sub...you will notice I put in some alerts.  On the second pass thru this page where I "should" be changing the session variable...I will see the "inside session 2" message... so I know it is making it to the right place and that the session should be resetting, but it just isn't happening.  

Could this be a setting in IIS?

are you sure this is the only place where you are setting the session variable? If you want to retain the session varaible, there is no need for this statement
>>Session("MyCurrentCustomer") = Session("MyCurrentCustomer")
try this code
        If Request.QueryString("Customer").Length > 0 Then
            Session.Item("MyCurrentCustomer") = Request.QueryString("Customer").ToString
        End If

Just to try... I commented out:

'Session("MyCurrentCustomer") = Session("MyCurrentCustomer")

And I get the same result

Yes... I did do a search on my entire project...and mycurrentcustomer session is not being set any other place.

Good suggestion, Rejojohny.
If you want to test whether the Session is being set elsewhere, just change the URL while on the page to a different customer number and postback. If that works (you will need to call DoSessionStuffHere() on each postback, though), then Rejojohny is probably correct--that Session("Customer") is being modified elsewhere. But, even if it is, your forced call to DoSessionStuffHere() should reset it to the QueryString value that applies to the current postback.

-- Jon500

Are you also certain that your url is well-formed? I've seen programmers make mistakes with the querystring arguments on postbacks (for example, misspelling "customer", or forgetting a "&" delimiter). Just another thought... It's unclear to me what you're posting back FROM, so I thought I'd suggest this.

-- Jon500

I agree with you... I totally took out the session=session

Here is what I have now:

Private Sub DoSessionStuffHere()

        If Request.QueryString("Customer").Length > 0 Then
            Session("MyCurrentCustomer") = Request.QueryString("Customer")
        End If

    End Sub 'DoSessionStuffHere

Problem is now... when the page is loaded... I get the error: Object reference not set to an instance of an object.   And it points to the .Length > 0 line.

Thoughts?

Try testing for Request.QueryString("Customer") = "". But using the .Length property, you're making an assumption that it the QueryString("Customer") can be resolved to an object.

Does that fix it?

-- Jon500

Sorry--I meant "By using the .Length property..."

When I try to use:

Private Sub DoSessionStuffHere()

        If Not Request.QueryString("Customer").Length = "" Then
            Session("MyCurrentCustomer") = Request.QueryString("Customer")
        End If

    End Sub

I get the error: Input string was not in a correct format.

here is my code now:

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        DoSessionStuffHere()

        If Request.QueryString("Customer") Is Nothing AndAlso Session("MyCurrentCustomer") Is Nothing Then
            Response.Write("<script> alert('In order to view Regular Contracts a Customer must be chosen first.'); window.location = 'default.aspx' </script>")
            'Response.Redirect("default.aspx")
        End If

        If Not IsPostBack Then

            DoSessionStuffHere()

            If Request.QueryString("Customer") Is Nothing AndAlso Session("MyCurrentCustomer") Is Nothing Then
                Response.Write("<script> alert('In order to view Regular Contracts a Customer must be chosen first.'); window.location = 'default.aspx' </script>")
                'Response.Redirect("default.aspx")

            Else
            ..........blah
            End If
        End If

End Sub

Private Sub DoSessionStuffHere()

        If Not Request.QueryString("Customer") = "" Then
            Session("MyCurrentCustomer") = Request.QueryString("Customer")
        End If

    End Sub

Thougths?  

here is the page behavior:

One thing:
You're now making a call to DoSessionStuffHere() every postback AND ALSO when IsPostBack is false. You only need to do the first DoSessionStuffHere() call in your Page_Load.

-- Jon500

Load home page

Click on John's contracts

First page load of contracts page:  customer=john

Session mycurrentcustomer=john

Click on link to homepage

Click on Jim's contracts

Second page load of contracts page: customer=jim

Session mycurrentcustomer=jim

Click on link to homepage

Click on a link (that is basically like a back button) and session of mycurrentcustomer=john again... where did jim go?

ok..took it out of the ispostback

Wait! Please tell more about "Click on a link (that is basically like a back button)..."
What does the URL of the page look like when you click that?
And what exactly is this "basically like a back button" link doing? Is it a LinkButton control, or something else?

-- Jon500

still the same problem

I cleared my application pool as a "reach" for something to do...and it make a different

excuse me... did not make a difference

I'm trying to put my application in simple terms to understand....but here is exactly what happens:

There are links along the left that let you navigate to parts of the application.  If a user comes to the site and trys to click on contracts they will get that message shown above that tells them they must select a customer first...and it bounces them back to the homepage that has some parabolic searching (dropdown boxes filled from sql tables).  Once the narrow down to a customer then are automatically directed to the contracts page.  If the user then click on the homepage, then click on the contracts link (from left menu) they will see the customer they just searched on.  But, if they click on the homepage (from left menu) and do the searching function again, and select a different customer, again they are bounced to the contracts page and the new customer information is displayed.  BUT... if the user clicks on the homepage (from left menu) and then clicks on the contract link (from left) they should go back to the contracts page and see customer #2 that they searched for, but the user will see customer #1.

I hope that helps?

I think it helps. Then I would like to ask: What is the code-behind for the Contract Link on the Home page?

-- Jon500

That shouldn't matter...as there is no session variable information set or changed there.

just a datagrid...with some <asp:hyperlinkcolumns />

Well, it could matter if the URL was being constructed there to include a Customer value. Is it? If not, does it just redirect to your target page with no QueryString information?

-- Jon500

The links on the left menu contain to querystring information

while the datagrid on the homepage has a datagrid that has a column that looks like this:

<asp:HyperLinkColumn
            HeaderText="Contract Review"
            HeaderStyle-BackColor=#003366
            HeaderStyle-ForeColor="#ffffff"
            HeaderStyle-HorizontalAlign="center"
            DataNavigateUrlField="Customer"
            DataNavigateUrlFormatString="Contracts.aspx?customer={0}"
            DataTextField="Customer"
            DataTextFormatString="Review"
            ItemStyle-HorizontalAlign="center"
            Visible="true" />

excuse me... The links on the left menu contain NO querystring information

"DataNavigateUrlFormatString="Contracts.aspx?customer={0}"
appears to be a querystring URL.

May I ask a simple question? When you click that link from the Home page and you get Customer 1 instead of Customer 2, what exactly is the URL for the target page? In other words, are you seeing a QueryString with Customer=1???

Thanks,
-- Jon500

The URL is : Contracts.aspx?customer=AAA11123

If I put in some alerts to show me the value of the session, it displays the proper customer (ie AAA11123)...even on the second pass.  But as usual...if I click on the homepage link on the left menu...and then click on the contracts link on the left menu... I should see customer AAA11123's contracts... but I see the first customer that I searched on.

I tried putting in a session.abandon in my DoSessionStuffHere sub... but that seemed to screw everything up

I'm trying to understand.
Contracts.aspx?customer=AAA11123

is the URL for the Second customer?
And you're saying that when you redirect to your page with this URL
Contracts.aspx?customer=AAA11123

the contracts.aspx page is displaying information for a customer other than AAA11123?

Thanks,
-- Jon500

I think I found the problem... the session is holding, but my

ViewState("myData") = dsItemGrid

is not changing... so when the contracts.aspx page is displaying it doesn't know to rebind with the new customer information?

Well, this is the first mention of ViewState("myData"). I can't possibly help until I see more source code. That is why I was asking about how you are navigating to the contracts.aspx page from the home page. You said it was plain links, then I saw a querystring value embedded in the grid's hyperlink column, and now there is a new issue possibly with ViewState.

You still haven't answered my question about the customer ID in the querystring. If the querystring is wrong, then the page is not ever going to display the correct customer.

If you are realizing that the customerid is wrong in the querystring, you should be able to work backwards to determine how that URL is being requested and how the (wrong) querystring value is being assigned. Knowing this should allow you to solve the problem.

Keep me posted.
-- Jon500

I don't think the problem is the session variable at all.  I think that is working now.  So your going to get credit for your suggestions.  My problem I think is in rebinding the datagrid.  If I take my binding code that WAS inside of the

If Not IsPostBack Then

End IF

and put the code in just PageLoad... it almost works.  After I follow the behavior described above...and get to the second customer.  I click off the page can come back...the first customer grid info is displayed, but NOW if I hit the refresh but...the second customer then appears.

So... somehow I have to force the pageload code to work everytime...????

Do you think I need to put my datagrid binding code in the regular pageload or ispostback or not ispostback?

or maybe in two of the three?

Hi,

I haven't see your "binding code", but you are correct that the page won't persist binding across pagebacks unless the ViewState is handling persistence for you, and that depends on your EnableViewState settings, etc.

I think the key, in all cases, is whether the correct ID is getting to your page by way of the QueryString value. You are correct that Session() is consistent (unless, as you already know, you overwrite it or the Session expires or--which is opening a whole new can--you are load-balanced to another web server that doesn't have access to session state).

It's unclear to me why the refresh is causing another customer to appear, but when you do a refresh, remember that IsPostBack will be true.

I'll be happy to continue to troubleshoot--I just need info from you!

Regards,
-- Jon500

   Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        DoSessionStuffHere()

        If Request.QueryString("Customer") Is Nothing AndAlso Session("MyCurrentCustomer") Is Nothing Then
            Response.Write("<script> alert('In order to view Regular Contracts a Customer must be chosen first.'); window.location = 'default.aspx' </script>")
            'Response.Redirect("default.aspx")
        End If

        If Not Session("MyCurrentCustomer") = "" Then

            Session("ConnProvStr") = "** my connect string **"

            viewstate("sortexpression") = "CUSNAM"
            viewstate("sortdirection") = " ASC"

            ReadExpenses()
            GetCustomerData()

            btnUpdateAll.Attributes.Add("onClick", "javascript:return confirm('Are you sure you want to make these changes?')")

            dgAnalysis.CurrentPageIndex = 0

            ProductTypeFilterChange(sender, e)

            Dim dsItemGrid As New DataSet

            'Add a table to the dataset
            dsItemGrid.Tables.Add("Items")

            'Add columns to the dataset
            dsItemGrid.Tables("Items").Columns.Add("CUSNUM")
            dsItemGrid.Tables("Items").Columns.Add("NAME")
            dsItemGrid.Tables("Items").Columns.Add("ADD")
            dsItemGrid.Tables("Items").Columns.Add("MASPRICE")

            ViewState("myData") = dsItemGrid

        End If

        lblSubmitted.Text = ""

    End Sub

    Private Sub DoSessionStuffHere()

        If Not Request.QueryString("Customer") = "" Then
            Response.Write("<script> alert('inside session') </script>")
            Session("MyCurrentCustomer") = Request.QueryString("Customer")
            Response.Write("<script> alert('" + Session.Item("MyCurrentCustomer") + "') </script>")
        End If

    End Sub 'DoSessionStuffHere

#End Region

Simple question:

Is this: If Not IsPostBack Or IsPostBack Then

the same as just putting code in Page_Load?

I still can't tell from the code above HOW you are getting the customer data. I assume it's in your GetCustomerData() function, but I can't see into that.

Why are you store grid data in ViewState("mydata")? Do you use ViewState("mydata") anywhere???

-- Jon500

Here is the customer bind:

Private Sub ReadExpenses()

        Try

            Dim strConnection As String = ConfigurationSettings.AppSettings("my conn string")

            Dim strSQLcommand As String = "SELECT * FROM mytable WHERE Customer = '" + Session("MyCurrentCustomer") + "'"

            Dim objConnection As New SqlConnection(strConnection)
            Dim objAdapter As New SqlDataAdapter(strSQLcommand, objConnection)
            Dim dsContracts As New DataSet

            objAdapter.Fill(dsContracts, "dtContracts")

            Dim dvContracts As New DataView(dsContracts.Tables("dtContracts"))
            dvContracts.Sort = viewstate("sortexpression") & viewstate("sortdirection")

            dgContracts.DataSource = dvContracts
            dgContracts.DataBind()

            objConnection.Close()

        Catch ex As Exception

        End Try

    End Sub

Yes, I use view state.. because I have a nested datagrid

I know its probably not the right answer.. but what if I was to put in some code to do an auto refresh in my page_load?

You're right--auto refresh is a terrible approach.

You need to focus on the URL and ensure it's correct.

-- Jon500

I went thru the entire URL process and it is correct.

For those that may look at this someday...

I resolved this problem with something that isn't pretty:

Private Sub DoSessionStuffHere()

        If Not Request.QueryString("Customer") = "" Then
            Session("MyCurrentCustomer") = Request.QueryString("Customer")
            Response.AppendHeader("Refresh", "0; URL=http://micdev/application/SpecialPricing/RegularContracts.aspx")
        End If

    End Sub

I causes the page to refresh (yuck!), but it works.

Jon500...thanks for your help!

I would rather see you add CACHE headers to your page to expire the content. I just thought about that. Caching can be established on the page and I am wondering if you are subclassing a page object that is adding a special CACHE header that is persisting your content. I really would get rid of this refresh idea.

-- Jon500

LOL... I just saw that:

Response.Cache.SetCacheability(HttpCacheability.NoCache)

On this question: http://www.experts-exchange.com/Programming/Programming_Languages/Dot_Net/Q_20995101.html?query=automatically+refresh+.net&clearTAFilter=true

That works perfectly!

Great! So you should be pretty happy right now. :)

Whew! (As I wipe sweat from my forehead...)

Regards,
-- Jon500

Yeah...very happy...gheez... didn't think this would be such an issue.  Thanks for the help thou!