Automatically checking a session value in every page_load
I have an application with lots of pages. I'd like to know if there is a way to have each page check for a particular session value before/during the page_load event?
I know I can manually code the check into each page, but is there anything a little more advanced that can be done so that I only have to code it in once?
I know I can manually code the check into each page, but is there anything a little more advanced that can be done so that I only have to code it in once?
ASKER
Hi spongie
Could you please provide a code example for option 1? In some of my pages I use code-behind, in others I code the server-side stuff directly in.
Would option 1 work with my existing approach?
Could you please provide a code example for option 1? In some of my pages I use code-behind, in others I code the server-side stuff directly in.
Would option 1 work with my existing approach?
First you need to create a base class for your webpage like below:
-------------------
Imports Microsoft.VisualBasic
Public Class BasePage
Inherits Page
Private Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Response.Write("Hello World")
End Sub
End Class
-----------------
Then on your Code behind files:
-----
Partial Class _Default
Inherits System.Web.UI.Page
End Class
-------
Or using inline code (take note of first line):
-------
<%@ Page Language="VB" Inherits="BasePage" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
</div>
</form>
</body>
</html>
-------
-------------------
Imports Microsoft.VisualBasic
Public Class BasePage
Inherits Page
Private Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Response.Write("Hello World")
End Sub
End Class
-----------------
Then on your Code behind files:
-----
Partial Class _Default
Inherits System.Web.UI.Page
End Class
-------
Or using inline code (take note of first line):
-------
<%@ Page Language="VB" Inherits="BasePage" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
</div>
</form>
</body>
</html>
-------
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
Oooops, i type later ;)
there is another way that is the best is using HttpModules,
so it can handle all http requests, and when you write one http modules there are no places to change.
there is another way that is the best is using HttpModules,
so it can handle all http requests, and when you write one http modules there are no places to change.
I would use http modules to do this
ASKER
Okay I get the class approach. Can someone tell me a little more about modules? I'm all for not repeating code!
http modules :
| | | |
http request ------> | http module 1 | ------> | http module 2 | ---------> Http handler( aspx handler)
| | | |
| | | |
http request ------> | http module 1 | ------> | http module 2 | ---------> Http handler( aspx handler)
| | | |
SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
Thanks for the insight there. I'm actually using VB, but I'll read the article anyway in the morning and see if I can figure my way through it.
Unless someone attempts it here first of course... :-)
Unless someone attempts it here first of course... :-)
ASKER
Before I start reading the page about creating a httpModule, can I just clarify one thing? There is one page in my application that will not require this httpModule affecting it, and that is the file the module will redirect the user to (same as the authentication process). Will this work okay, or will I end up in a never-ending redirect cycle?!?
ASKER
Hi All
I'm going to have to request help on this one again unfortunately as I'm in way over my head.
Can anyone assist in helping to create the module that will perform a check to see if a session value exists before allowing the page to load?
As this exists alongside authentication, can the module expand on the functionality already present for authentication? I see in Intellisense that there's a HttpApplication.AddOnAuthe
Is this the correct approach still, or am I better off creating a fresh module from scratch to work independantly?
I'm going to have to request help on this one again unfortunately as I'm in way over my head.
Can anyone assist in helping to create the module that will perform a check to see if a session value exists before allowing the page to load?
As this exists alongside authentication, can the module expand on the functionality already present for authentication? I see in Intellisense that there's a HttpApplication.AddOnAuthe
Is this the correct approach still, or am I better off creating a fresh module from scratch to work independantly?
Im creating the code right now... give me a few minutes
ASKER CERTIFIED SOLUTION
membership
This solution is only available to members.
To access this solution, you must be a member of Experts Exchange.
ASKER
Thanks for that rodmjay. There's just one error thrown though. I think it's because there's no actual sub that is referenced in the PostRequestHandlerExecute.
Name 'context_PostRequestHandle
Line 20: AddHandler ctx.PostRequestHandlerExec
Name 'context_PostRequestHandle
Line 20: AddHandler ctx.PostRequestHandlerExec
ASKER
Also, if I wrap the class inside a namespace, do I need to include that namespace info in web.config? i.e.
<add type="MyNS.MyModule" name="SomeModuleName"/>
<add type="MyNS.MyModule" name="SomeModuleName"/>
yes, very true, delete the delegate for the postrequesthandler and you should be good, all you need is the prerequesthandler one. The web.config you are showing should work. if not, you will want to google httpmodule web.config and you can get the correct syntax.
ASKER
Okay I think it's plugged in. The problem is I get a browser error in Firefox:
>>The page isn't redirecting properly
>>Firefox has detected that the server is redirecting the request for this address in a way that will never complete.
Would this be because the module would affect EVERY page in the application? If so, I'd need the module to ignore login.aspx as that is the destination page for redirection after the session value has been checked.
>>The page isn't redirecting properly
>>Firefox has detected that the server is redirecting the request for this address in a way that will never complete.
Would this be because the module would affect EVERY page in the application? If so, I'd need the module to ignore login.aspx as that is the destination page for redirection after the session value has been checked.
I am a little unclear on what your application is supposed to do... you asked for something that checks for the session variable for each page... What I would do, which i cant go into much detail is user a marker interface for the pages that dont require to have session variable checked
Something like INoSessionCheck
This interface will have no methods, but in your logic, see if the page implements this interface, if so skip the Session checker logic. you will also probably have to use the postrequesthandler to do this, since the page object isnt created at this phase in the request. I would start a new thread for this if you have any questions and ill help you the most i can.
Something like INoSessionCheck
This interface will have no methods, but in your logic, see if the page implements this interface, if so skip the Session checker logic. you will also probably have to use the postrequesthandler to do this, since the page object isnt created at this phase in the request. I would start a new thread for this if you have any questions and ill help you the most i can.
ASKER
Sorry for any confusion. I am using forms authentication on the pages, starting from login.aspx
The login page verifies the user then creates an authentication ticket that contains the user's role. On top of that I then store an integer in a session variable which represents further information about their account.
Now, forms authentication automatically checks for the authentication ticket prior to each page loading, but, I wanted to also incorporate a check for the session value at the same time. This was where I presumed a httpmodule would come in.
I know that in each page I could do:
sub page_load(....)
if not session("myVal") is nothing then...
but I wanted to avoid having to re-code that on every single page.
The login page verifies the user then creates an authentication ticket that contains the user's role. On top of that I then store an integer in a session variable which represents further information about their account.
Now, forms authentication automatically checks for the authentication ticket prior to each page loading, but, I wanted to also incorporate a check for the session value at the same time. This was where I presumed a httpmodule would come in.
I know that in each page I could do:
sub page_load(....)
if not session("myVal") is nothing then...
but I wanted to avoid having to re-code that on every single page.
Thats fine. Did you try my proposed solution?
ASKER
Okay rodmjay, I posted this as another question. Please let me share the rest of your knowledge on this matter! :-)
https://www.experts-exchange.com/questions/21924662/Using-a-marker-with-a-httpmodule-to-check-for-a-session-variable-prior-to-page-load.html
https://www.experts-exchange.com/questions/21924662/Using-a-marker-with-a-httpmodule-to-check-for-a-session-variable-prior-to-page-load.html
ASKER
Sorry to be a pest, but could you please take a look at the follow-up question and let me know your thoughts? Thanks.
1) Create a page class with your session value checking code for page_load event and let all of your pages inherit from it.
2) Use master pages.
:)