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Keeping data across a redirect

I have a page with a form that accepts a list of account numbers into a text box, a bulk search essentially.
This does posts to the server, does a validation exercise and then if sucessful redirects to a display page.
Currently the list is added as a GET variable in the URL to the display page. This is limiting in that it means users can mess with it and larger data sets may be a problem. It also allows for a bypass of the validation but this is accounted for.
I see 2 general solutions which are basically variations of 1 theme:
Save the list to a DB and pass a key to load this to the diplay page.
Save to MemoryCache and again pass the key to the display page.
Based on these options it seems that 1. is better if I need multiple IIS node but needs manual cache cleanup where 2. will clean it's self up but may be a problem if I need to scale. This will be an intranet applcation so scale will probably not be required.
Is there a "industry standard" approach to this class of problem. I'm coming from the winforms world where keeping track of state wasn't an issue.

I don't think you really have to redirect to the display page at all. From the controller that gets the user input and prints the result just return the View that should render the results like:
public class SearchController : Controller
{
public ActionResult SearchForAccounts(string[] accounts)
{
var searchResults = db.Search(accounts);
return View('ResultsView', searchResults);
}
}
If you really really need to redirect, I guess you chould save the results into the application Cache and later if you need to scale you could use a Redis Cache provider for example, but again you should be able to show the required view.

Whether it's Webforms or MVC, I recommend not getting into the pattern of separating validation/processing and results into separate pages.
I'm guessing that if the data is invalid you want to put it back on the page so the user can edit it. (That's a guess inferred from what you're asking.)
You can post the data, and then if the data is valid then the "result" page shows the results. If the data isn't valid then the page can re-render the input form, populate it with the original inputs, and display a validation error. That way the user can modify their original input and try again. (Just be sure to escape/unescape if you're taking user input and reflecting it back onto the page.) That's easier if the form is a partial view (MVC) or a user control (Webforms.)

ASP.NET MVC DropDownList alternative

I'm using a dropdownlist for a field on a form, but with large amount of data retrieving from the server, makes the load of the page extremely slow. Do you have a solution to this problem?

Implement a free text like solution like:
when the user clicks on the text input you can pop up a dialog to query the users (you can add an additional search field and then load in a table the results, add a click on a row should add the user to the main form)
true free text expirience with deferred loading the matches like Facebook search does

Saving data on a web page when switching from one page to another in ASP.NET?

I'm new to ASP.NET. I'm designing a user interface in Asp.NET and C# where the user can login and then launch an application. When using this application the user has to fill out a form that is 10 pages long.
So, I have used navigation menu and designed the interface in such a way where every page is different menu item and it is a static menu. The user fills out the details on the first page of the form and saves it and the data gets saved in the database.
The problem is he moves to the other page by clicking the menu tab; when he comes back to the first page by using the menu tab for that page all the filled in data is gone and he sees a blank page. I know that is how it works but I want it in such a way that in one sitting when he is filling out the data on the second page (after filling the data on first page) on reverting back to the first page he should be able to see the data that he had filled out.
What concept can I use? I'm not sure view state will be helpful in this scenario.

You should look into using the Session State variable for storing his information over the entire session. If the user is logged in you should think about storing his information that he enters in a database and having a Boolean state of "ApplicationFinished" to check if he has finished it or not. Otherwise I would have a call on each page to retrieve information from the database that has already been added, so that he can fill out information at different sittings or all at once.
http://msdn.microsoft.com/en-us/library/ms178581.aspx
Session State may be too long term for you, and if that is the case do some research on ViewState. There are a lot of different ways to tackle a problem like this. It all depends on which technology will fit your needs the best.
http://msdn.microsoft.com/en-us/library/ms972976.aspx
Also, if you're using a tab system think about using the AJAX tabs so that the data will remain on the forms even while tabbing through the different tabs.
http://www.dynamicdrive.com/dynamicindex17/ajaxtabscontent/

Well, if you are write the data on database, i guess the best (fast) workaround is to add a column named "completed" to the table the hold this informations. If the flag "completed" is not setted to 1, you load the database information and fills the page controls.
When you create a new record in the database, get the ID of the record and set it on Session. If the user gets back to the first page (previous page), you can recover the information ID and load the data.

As long as you are learning new things... add jquery to the list and leverage the JQuery Wizard Plug In. It will allow you to integrate your "10 page form" into a single unit, which can then be sub divided, routed and managed more easily. You can leverage AJAX to save each step, while offering built in navigation and validation methods.

I would suggest that you switch to using client-side javascript to control your tabs. That way your form data stays in the fields when you switch back and forth between tabs. You can use javascript buttons to guide the user from tab to tab.
I've done this using JQuery. I actually had 150 fields that needed to be captured (they were all required). I group like data on different tabs and then had buttons ('< Previous', 'Next >') which would activate different tabs.
When they are done, then display the 'Save' button.

This not be what you are looking for, but if your problem is that you want all of the input of a previously filled page to show up when a user navigates back to it, and you have already saved all that information, then you can try something like this:
HTML
<input type="text" id="yourID" name = "yourName" value = "<%=data%>"/>
Then all you need to do is set data to public in the code behind. Then to get the value for data just make a call to your database.
Make sure that you make data empty on the init call public string data = ""; or whatever type it is. This way if there is no info, then it will be blank, and if there is saved info, then it will be filled in.
You can also attempt to pass all the data through params in the url like so:
C#
Response.Redirect("webpage.aspx?data=" + data + "&data1=" + data1);
Or though javascript:
window.location = ("webpage.aspx?data=" + data + "&data1=" + data1);
To get the request do this:
if (Request.Params.AllKeys.Contains("data"))
{
data = Request.Params["data"];
}
This way is less ideal though if there is a lot of data being passed.

Filtering Pane, ASP MVC 3

My plan is to create a a two-pane page using ASP MVC 3. The left pane should be a small filter pane and the right the main content, showing a list of objects (say products).
Initially all products will be shown since no filter is applied. When selecting "only red", only red products are shown in the list. When further selecting a price range, only products in that price range will be shown.
Functionally the plan is to implement the filtering pane as a treeview with checkboxes (to be able to drill down to more and more specific filtering options), graphically it will probably be enhanced in some way to improve usability.
What is the best way to implement the coupling between the filter pane and the main list? Everything should work server side, but should of course use javascript (jQuery) when possible for direct feedback.
The simplest way is probably to make it closely coupled solution, calling a specific Asp MVC action using a custom-built javascript (with fallback to a form post). Doable enough, sure, but how to make the solution reusable? Also it would be nice to not loose all filtering data when navigating forward and back, i suppose GET arguments is the only decent way to do that?
Are there any best practices, any guidelines or anything to base this on to make a nice modular structure for filtering.

Victor, I recently had to solved this same problem. I'm not promising it's the best way but it's pretty clear and should even work well in case JavaScript is disabled (who even does that anymore?).
Create a that calls the action with all the field-selectable search options like "only red".
To that same form, add empty, hidden value for the things not directly as fields (paging, sorting...)
Setup your form with the excellent and very easy to use JQuery.Forms (http://www.malsup.com/jquery/form/) to make you form submit via JQuery (all your form values will be passed as JSON on form submit).
Make your back/next/paging/sorting links pass their individual values via query (no-JS fallback) and use JQuery to capture their click events. The JQuery click events on those links should assign the value of the value passed by the link (page number, sort column name...) to the corresponding hidden field in the form and call submit (with thanks to Jquery.Forms will submit via AJAX).
When you configure JQuery.Forms, you can define a callback method. In the callback method take the result (the HTML returned by your action that should contained your filtered+sorted+paged result) and replace the document (or DIV if you used a partial action + view) with that.
The result is a JQuery solution that works when JS is off. You also have very minimal JS code to write other than wiring the event handlers.
I'm not sure if it will be helpful but in MVC 3 you have access to a property called IsAjax from the view so you can do specific things to server a slightly different view when called from AJAX.
Cheers

Suggest something for storing history

i have a ajaxified list page showing some list of items i am using a user control for filtering the content of the list page there are multiple filters in the user control what i want is if a user applied more than one filter than navigate to other page and press the back button the applied filters should be there in active state.
can any one please suggest me something how to achieve this.

You should put the filters in the query string because:
(1)It's not secret data.
(2)When user click "back" button of the browser, of course he wants the list is well-filtered, instead of that he need to filter the list again. Also sometimes he may copy the url in the address bar and sent it to others.
Format the filters' info in a proper way, e.g. "filter1=name&filter2=price", and deal with the query string in Page_Load if there is a filter.

One way is using cookies.
Store the values in a cookie, and read them back with javascript when the user hits the back button.
Or use the querystring like #Danny says. Why didn't I think of that right away :)