I have a search page where a user can enter search parameters and click a search button. The ASP application will then send the data to a stored procedure in a SQL 2005 database. The results of the database search are then sent back to the ASP application and displayed in a gridresults page. The user then has an option to go back to the search page and do another search. The issue is that no matter what they enter, they do not get any results. I think the session variables are not clearing out. I tried to do this:
Session["Name"] = null;
and
Session.Remove("Name");
I did both of these when the search page loads and when the button to go back to the search page is clicked. Neither seems to work. Any ideas?
More than likely, you are clearing the session variables, but inadvertently setting it again somewhere else. Recheck every place you set the session values.
Related
There is some generated contents with the links on an ASP.NET page, which is created after the user inputs values and hits a button. The links take the user to another page.
When the user hits the Back button, the generated content is gone as the page returns to its initial state with the inputs cleared and generated content not there.
Is it possible to preserve the state of the page after its content has been generated and restore it after the Back button was clicked?
I think you can you can you temporary cookies.
and on load check whether cookie is exists or not.
Save the inputs in the session, so that the page will know how to correctly render on later requests. Even better, have the first code that runs when the data is submitted redirect to new page with a URL parameter that you use to know which links to show. This is a called a POST-REDIRECT-GET pattern.
I'm creating a form that a user has to completely fill out before they are able to register for a website. What i'm trying to counter is if the user gets to url of the second page by accident. I've tried using if(!isPostBack) and then inside the if statement redirecting them to the first page but that only works the first time, and the user can never hit the second page that displays their details when they click on the submit button because the second page is now a post back. Any help would be greatly appreciated!
There are several ways of doing this. You could use Session to store user progress. Also, if you have a long multi-page form you could have a master table for your form in the database that tracks user progress (column named ProgressPage, for example).
I am using VS 2005, C# 2, ASP.Net 2.0
I am unable to find out how to track that user pressed F5/Ctrl+F5/ Open a new Window(Ctrl + N) in ASP.Net.
I know that there is a Page.IsPostBack property, which tells that a page is loaded in response to an action taken by user.
I am just curious to know, that why isn't there a property as IsRefresh or Page.IsRefresh in ASP.Net, which will return true,
whenever user takes any of the above actions.
Is there a way to know this?
Actually my problem is that i have a DLL using which all of my aspx pages are inherited, I have to
insert some values in a table whenever the page is opened for the first time that's it, if user just opens the page or do not take any action,
an entry should be inserted into the database, but as far as I have tried, I controlled it anyhow using the Page.IsPostBack property, but I got stuck
in the refresh case, as it is inserting records unconditionally.
Similar to using a function in Global.asax (as others have suggested) you could use a session variable "flag". When the page first loads set a session variable and then just check against it in your page load function:
if (Session("visited") != "true"
//page has not been visited, log visit to DB
Just make sure you set the session flag sometime after the above check during the page load.
It won't be exact (sessions can timeout while a page is active, users can completely leave the site and come back in the same browser and the session stays alive, etc) but for your tracking it is much better than counting every page hit in the DB.
Perhaps you want the Session_Start method in the Global.asax file, which will be triggered once at the start of each user session?
In your Global.asax file, add or edit the method:
void Session_Start(object sender, EventArgs e)
{
}
why isn't there a property as IsRefresh or Page.IsRefresh in ASP.Net
Because ASP.NET cannot possibly know. The browser does not send any information that could allow it to determine whether the page is being requested due to a refresh or normal load. You will need to reconsider your requirements: what is the actual purpose of the database logging?
Session_Start method in Global.asax file is fired every time when a browser session is started. You can use this method to count number of unique users on your website.
Session_End method in Global.asax is fired when a session ends (explicitly or timedout). So you can decrement the count here.
Hope the above to example uses of these methods helps you understand how you can use them.
Because of the stateless nature of HTTP protocol there is no way to tell apart the initial load from the refresh
As has already been said. This isn't possible. A request issued due to a refresh is no different to a request issued the first time the page is loaded.
It sounds to me like you are trying to track page views somehow. This is certainly possible though it will require some work on your part. Your best bet is probably to log the URL of the page. You may also want to include the query string in order to differentiate between page loads for different pieces of data (if this happens in your application). You will also want to log the ID of the current user, and the ID of their session.
You can then make sure that you don't insert two page views for the same user for the same page in the same session, effectively filtering out any reloads of a page.
You do need to be aware that this isn't the same as detecting a refresh, what you are detecting is two page views in the same session, this could be a refresh, or it could be use of the back button, or just reloading from the address bar.
My suggestion would be to create a cookie on very first load, then on Page_Load check to see if the cookie exists. If it does, don't insert the record. You can use Session_End to destroy or create the cookie as someone suggested if that works with your application's architecture.
First of all, thanks for reading.
I will describe my situation as explicitly as I can.
I have a page where users can leave comments.
Here's the commenting flow
A-1. 'comment' button is clicked
A-2. a modal popup with a textbox is shown using ModalPopupExtender in ajaxtoolkit.
A-3. User types a comment in the textbox, and click "ok".
However, when user is not logged in, expected behavior changes.
B-1. 'comment' button is clicked
B-2. a Login modal-popup with id & pwd textbox is shown.
B-3. User types ID & pwd, and click ok.
B-4. Comment-modal-popup is shown
B-5. user types a comment and click ok.
I have a PROBLEM handing this case.
When B-3 occurs, page is posted back, i log the user in, update session object, and I Response.Rediect() the page to itself to display correct logged-in status (i have to..).
After redirect, in Page_Load(), I need to check some values to show Comment-Modal-Popup.
But I'm not sure how..
Here's what i considered
ViewState
i just can't use it since the page was redirected not posted back.
QueryString
I could have add "showCommentPopup=1" on URL when redirecting, but that will leave unwanted QueryString in URL. I don't want users to misuse it.
Session
I actually used Session object. Before redirection, I set Session[ "ShowCommentPopup" ] to true. In Page_Load() if it is set, i remove it and show the popup.
using Session like i did doesn't work correctly when user opens same page in multiple tabs.
user opens two tabs(in Firefox) with same URL
user follows steps from B-1 to B-3 in first tab.
before the page is redirected between B-3 and B-4, user refreshes second tab.
if the timing is right, comment-popup is shown in the second tab.
I expect to hear great insights from stackoverflow..
I haven't tried this but I think if you store your ShowCommentPopup flag in the HttpContext.Items collection instead of the session and then use Server.Transfer instead of Response.Redirect you should be able to achieve the desired results.
HttpContext.Items is a dictionary that can be used to store data whose lifetime is the lifetime of the request. This means a second request from a different tab or window will have a different HttpContext.Items dictionary.
Server.Transfer is somewhat like Response.Redirect in that it allows you to load a "different" URL instead of the original. However, while Reponse.Redirect initiates a new request, Server.Transfer transfers the existing request to the new page on the server.
A better explanation of the differences between Response.Redirect and Server.Transfer can be found here.
Example
bool showCommentPopup = false;
if (HttpContext.Current.Items["ShowCommentPopup"] != null)
{
showCommentPopup = (bool)HttpContext.Current.Items["ShowCommentPopup"];
}
//...
HttpContext.Current.Items["ShowCommentPopup"] = true;
You've clearly thought your solutions through! I'm guessing the problem with the Session was that they could comment on a different page than the one they logged into. You could get around this by storing the session var, not as a bool, but as the page to show it on:
var uniqueString = this.ToString() + uniquePageID;
if (Session["ShowCommentPage"].ToString() == uniqueString)
//show modal & remove session var
Now your program only "breaks" when the user visits the same object in two different windows, logs in on Window #1, and refreshes on Window #2. And it's not really breaking since they wind up commenting on the same object either way.
The reason I used uniquePageID, is cause I'm figuring you have a template page ("showObject.aspx") with arguments on which to show ("showObject.aspx?objectID=3"). In order to make sure the comment is left on the same ID, it needs to be present in uniqueString
I have written an application in ASP.net, that is designed to let the user add records to a database. The page is set up that when a user adds a record, the ID number of the newly added record is set in session, the page Response.Redirects to a "Thank you for submitting" page, then redirects back to the original page to allow further edits. Users can also use the Back button on this screen to go back to the original record adding page, which allows them to make edits to the data.
However, I have found that storing the ID in session isn't a terribly good solution, as a user might try to create two documents in different tabs or windows. I have also tried setting the ID in a literal control, but this causes the problem that when the user uses the Back button, the literal control isn't set to the ID, and new records get added instead of one being edited.
Is there any kind of solution for this?
I'd recommend storing your ID in the QueryString. After the record is added, redirect to your "thankyou" page, which then I am guessing contains a link to the edit form which you will generate with the ID in the querystring. When that link is followed, the edit page shouild pull the ID out of the query string in order to load up the correct record to edit.
Your add and edit form can even be the same page, when an ID is provided in the querystring, your form knows to edit that record, otherwise your form adds a new record.
Silly question, why can the user use the back button to edit the data just accepted in a post?
If the edit previously posted data is a common scenario why not just redirect to a page when the data is accepted that lets them edit it. Then if the hit the back button they would be going back to the original "clean" insert/add new data page.
This would give the following flows
Add->[Post]->Edit->.....
Add->[Post]->Edit->[Back button]->Add->[Post]->Edit->[Post]->Edit....
Have you tried adding the ID in the querystring? Then you could read it, and add it to the session as needed (say on a user clicking the back button).
Seems like a lot of problems allowing editing of an object in a page rendered when using the back button. Would it be too much to give them an edit button instead?
The controls save their state in the ViewState. If you choose to use SessionState instead of ViewState to store the information, then the controls will save their state in the session state and it won't work properly with multiple tabs.
I have not yet found a way to bypass this issue while still using SessionState. Our solution was to use the normal ViewState.
I've tried storing the ID in the querystring (which is mostly fine for editing), but the problem with that is when the information is stored in session for when they use the Back button. If the user does the following:
User creates a record (1st record), the ID is passed along in the querystring, and temporarily stored in session.
User creates another record (2nd record), the ID is passed along in the querystring, temporarily stored in session.
User uses the Back button on the first record to go to the page that doesn't have the querystring.
It's probably a far-fetched scenario, but it's one that may happen. The only solution I have is to block the usage of the Back button to go back to the adding page, by using window.history.forward() in JavaScript. But this as a solution is terrible.
My question for you is why are you storing anything in the session to begin with? If you can avoid storing anything in the session, I think you will be better off altogether.
Having thought about this, does the following sound like a decent solution to the problem I outlined above?
When first adding a record, store a timestamp of when the add page was accessed in a hidden field.
This timestamp is passed through session when the user clicks save. Along with the ID.
If the user opens another tab at the same time and saves, then the new page's timestamp gets passed through session.
If the user tries to access the add page of first record (using the back button), the system looks up session, and sees if there is a timestamp, and whether it matches the one in the hidden field for that page.
If it doesn't match, then the user gets a prompt, and told to edit the record properly.
Does this sound reasonable, or too overly complex?