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ASP.NET MVC route to return user to origin from partial view

I'm using ASP.NET MVC in Visual Studio 2015. The app has the following structure:
MyApp
Controllers
Controller1
Actions
Create
Delete
Details
Edit
IndexPartial
Controller2
Actions
Edit
Controller3
Actions
Edit
Views
Controller1
Create
Delete
Details
Edit
IndexPartial
Controller2
Edit
Controller3
Edit
The app displays Controller1/IndexPartial view on the Controller2/Edit view and on Controller3/Edit. This partial view displays rows of data, each with Edit, Details, Delete buttons which take the user to the Controller1 views for those actions.
When the user is done with the Controller1 action, they need to return to Controller2/Edit or Controller3/Edit via the Back to List button or when the Save/Delete buttons are clicked. But how do we determine where the user originated? Did the user come from the Edit of Controller2 or Controller3?
We've thought of using a session variable. Can RouteConfig.cs be used to track the user's path and help determine where s/he should return? How do we do this via routes in MVC?
Thank you for your help.
Update: This is all done via the server; no JavaScript (Angular, etc.).

The routing engine has nothing to do with what you need. You need to track user navigation and a good way to do this is using ActionFilters.
You can create a custom ActionFilter that checks the UrlReferrer on its OnActionExecuted and decides how to redirect the request to the appropriate Controller/Action.
[Example]
ActionFilter
public class RedirectAfterActionFilter : ActionFilterAttribute, IActionFilter
{
public override void OnActionExecuted(ActionExecutedContext filterContext)
{
// Your decision logic
if (filterContext.HttpContext.Request.UrlReferrer.AbsolutePath == "something usefull")
{
filterContext.Result = new RedirectToRouteResult("Your Route Name", routeValues: null); // redirect to Home
}
base.OnActionExecuted(filterContext);
}
}
ActionFilter usage
[RedirectAfterActionFilter]
public ActionResult DoSomethingAndGetRedirected()
{
// Save, Edit or Whatever
//...
return new EmptyResult(); // no need to return since the user will be redirected by the filter
}
Extra: Read How to redirect from a action filter if you dislike to use Route names to redirect.

There are two aspects to this:
The "Back to List" link
The "Save/Delete" actions
As far as the "Back to List" link, your controller should be giving the view all the information it needs to produce a viable GUI. Pass an identifier (or even the actual return URL) to the view in the ViewBag as a dynamic property and let the view render the link to the destination.
For the "Save/Delete" actions, it depends on how they are implemented.
If it's all JS with http requests then the same concept above applies.
If you are posting back to the server however, the controller will have to do the redirection with something like RedirectToAction().

How about storing the previous location in a ViewBag and then populate your button href with the ViewBag content...
Or
You can use Url Referrer, which fectches the previous url that linked to current page.
Of course the best method will depend on your implementantion, without seeing your code those two are the best option that I can think of.

How to check current user's role in ASP.NET MVC 5

currently dealing with an interesting problem. I am building a website with three different user roles. When logged in, the MVC partial view shows navigation options for the users. I want to show different options depending on the user's role. In previous websites, I have used the following code to determine a role:
#if (Roles.IsUserInRole("intern"))
{
<li>#Html.ActionLink("Log Time", "Index", "Time")</li>
}
Unfortunately, when I attempted this in my current code, I got the message:
The Role Manager feature has not been enabled.
So apparently in the new MVC they disable the role manager by default and have a new way of doing it. No biggie. Searching the issue suggested that I enable the feature in web.config. I followed several instructions on how to do that (I promise I can google search) but it seems to mess with my SQL Server connection string, giving me errors that indicate it's trying to log in to a local db that doesn't exist rather than my Azure SQL Server. I've played around for a while and I don't know why this is the case.
Anyway, long story short, rather than work around and re-enable a vestigial Identity feature, how are you supposed to accomplish this in the new MVC? I can get the roles fine controller side with user manager, but I can't use that in a view. Similarly a Viewbag full of roles can't work because this is navigation on every page.
I appreciate all the help in advance, thanks everyone!

Just found the answer, I'll leave this up for other people dealing with this. The correct way to do this is:
#if (User.IsInRole("intern"))
This makes sense since MVC is moving away from Role based objects and towards User based objects.

I think it's not really a good idea to ask for the user's role all the time, too many requests are made.
It would be better to ask once and save it on a variable in Razor. Then just check that variable whenever you need it.
By the way, if the roles are different, you don't even want to ask if the user is in that role rather than another one. Rather get the list of roles in a list and check if the role indicated is in the list.
Example (I'm not sure it will compile, look a the idea):
#using Microsoft.AspNetCore.Identity
#using Microsoft.AspNetCore.Mvc.Localization
#inject UserManager<ApplicationUser> UserManager
#{
ApplicationUser currentUser = await UserManager.GetUserAsync(User);
var roles = await UserManager.GetRolesAsync(currentUser);
bool isIntern = roles.Contains("intern");
bool isExtern = roles.Contains("extern");
bool isFoo = roles.Contains("foo");
...
}
then, further on
#if (isIntern)
{
<li>#Html.ActionLink("Log Time", "Index", "Time")</li>
}
else if (isExtern)
{
...
}
You can control the role of the user as many times as you want without having to make other requests and it's all much more readable.

How to reload security principal user info or a partial view

I'm developing an aspnet mvc application and i have a problem to reload some data, i don't know if the problem is in the security principal info that every view contains or in my partial view that doesn't reload when some other view is shown.
I have a layout page that is used in my whole application, and inside this layout page i have this partial view code fragment:
#Html.Partial("_PartialActiveClient")
this partial view contains the next lines:
#if (User.IsInRole("HasClients"))
{
<p>An Active Client</p>
Change active client
}
else
{
<p>You don't have any clients<p>
Create client
}
So when a user creates an account for the first time, this user has 0 clients and doesn't belong to the "HasClients" role and the "you don't have any clients" message is shown, but when this user creates his first client, the user is added to the "HasClients" role by default in my controller. The problem is that the "you don't have any clients" is still there even if i change the views. In order for the other message to show, this user has to log out and then log in again.
So my question is, how can my users see the "An Active Client" message immediately after they create a client?

The roles are cached in a cookie , so you can force them to refresh by deleting the cookie. You need to refresh users role. Here is a ways
you can call this Roles.DeleteCookie(); and it will clear roles and reload it in the next request.
This is taken from this question page Refresh ASP.NET Role Provider

Just to clarify my comment to the answer provided by Tchaps. This is the code (not my original code, but make my point) to my solution, like i wrote in the comment, it's not elegant but i works, at least in my case.
// Add to role, save changes
await _userManager.AddToRoleAsync(userInSession.Id, roleHaveClients.Name);
await _userManager.UpdateAsync(userInSession);
// Sign out / Sing in
_registerManager.AuthenticationManager.SignOut();
await __registerManager.SignInAsync(userInSession, false, false);
// Redirect to another action
return RedirectToAction("someAction","someController");

Maintain the model lifetime in MVC application

I am new to MVC and I have very simple problem.
When user login to my application I need to create a specific object (model) for the user for eg UserObject.
This object is unique to current logged in user and should only be disposed when user click on logout.
I don’t know how to maintain the lifetime of the object. As if I create object in Action method of controller class then as soon as the request is finished I lose the reference of the object.
How this should have been done?

The lifetime of your models are only going to be as long as the request. So each time the user goes to another page or refreshes, the MVC framework is going to instantiate a new controller (and model within). Otherwise your server would have a ton of static objects floating around in memory which would use up a lot of resources and wouldn't scale.
In order to manage state, you are going to need to use other methods such as sessions/cookies and a database.
So let's say the user logs in via /User/Login. This routes the request to an action named UserController.Login().
Inside this action, it instantiates a UserModel.
public ActionResult Login(string username, string password) {
var userModel = new UserModel();
if (userModel.Authenticate(username, password)) {
// Setup your session to maintain state
Session["username"] = username;
} else {
return View("Login");
}
return View("LoginComplete");
}
You might want the user model to actually create the session, but I've shown it here for clarity.
The user model authenticates the user, and then you create a session just like you would in a traditional non-MVC site.
Then in subsequent requests, you will want to authorize the user, and use any session data you have to retrieve state information.
public ActionResult SuperSecretPlace() {
var userModel = new UserModel();
string username = Session["username"]
var user = userModel.GetUserByUsername(username);
if (user == null) throw new HttpException(401, "User is not authorized.");
return View("SuperSecretPlace", user);
}
In the action above, the UserModel might do something like query a database to retrieve the user's data so you can pass it in to the corresponding view.
If you want to make life easier, you might want to just use .NET's built in forms authentication:
http://www.codeproject.com/Articles/578374/AplusBeginner-splusTutorialplusonplusCustomplusF
For more info about the lifecycle of MVC:
http://www.dotnet-tricks.com/Tutorial/mvc/TbR0041112-Asp.net-MVC-Request-Life-Cycle.html
http://www.asp.net/mvc/overview/getting-started/lifecycle-of-an-aspnet-mvc-5-application

Actually what you are trying to achieve is passing model from controller to controller which is not possible. When an action is executed the context of the model object is disposed at the view and it can cannot be passed from controller to controller. You have to create a new object repopulate it and use it to achieve the goal in different controller.If you need the data to be persisted you can use sessions but still you need to create an object of the model in every controller.
The following image is for your reference as to see what to use when passing data between model-view-controller. Please feel free to ask if you need more information on this.

As opposed to the other aswers I would not use session as it has quite some disadvantages (scalability, pessimistic concurrency which blocks concurrent calls, app pool recycling...). Why you should not use session is documented in a lot of places like here or here.
Instead, I would store it in a cookie.
However, be sure to not store confidential or sensitive data. Whatever you use (cookies or session), it can be tampered with or stolen. If you are dealing with sensitive information, you need other solutions. Read also more about secure cookie solution here.

What is a good method for preventing a user from submitting a form twice?

I have a purchase page and I don't want the user to be able to refresh the page and resubmit the form once they get to the 'order complete' page because it automatically sets them up in our system via database values and charges their card via paypal (only want these to happen ONCE)... I have seen some sites that say 'Don't hit refresh or you will get charged twice!' but that is pretty lame to leave it open to possibility, what's a good way to only allow it to be submitted once or prevent them from refreshing, etc?
PS: I saw a few similar questions: PHP: Stop a Form from being accidentally reprocessed when Back is pressed and How do I stop the Back and Refresh buttons from resubmitting my form? but found no satisfactory answer... an ASP.NET MVC specific answer would be ideal too if there is a mechanism for this.
EDIT: Once they click submit it POSTS to my controller and then the controller does some magic and then returns a view with an order complete message, but if I click refresh on my browser it does the whole 'do you want to resend this form?' that is bad...

The standard solution to this is the POST/REDIRECT/GET pattern. This pattern can be implemented using pretty much any web development platform. You would typically:
Validate submission after POST
if it fails re-render the original entry form with validation errors displayed
if it succeeds, REDIRECT to a confirmation page, or page where you re-display the input - this is the GET part
since the last action was a GET, if the user refreshes at this point, there is no form re-submission to occur.

I 100% agree with RedFilter's generic answer, but wanted to post some relevant code for ASP.NET MVC specifically.
You can use the Post/Redirect/Get (PRG) Pattern to solve the double postback problem.
Here's an graphical illustration of the problem:
What happens is when the user hits refresh, the browser attempts to resubmit the last request it made. If the last request was a post, the browser will attempt to do that.
Most browsers know that this isn't typically what the user wants to do, so will automatically ask:
Chrome -
The page that you're looking for used information that you entered.
Returning to that page might cause any action you took to be repeated.
Do you want to continue?
Firefox - To display this page, Firefox must send information that will repeat any action (such as a search or order confirmation) that was performed earlier.
Safari -
Are you sure you want to send a form again?
To reopen this page Safari must resend a form. This might result in duplicate purchases, comments, or other actions.
Internet Explorer -
To display the webpage again, the web browser needs to
resend the information you've previously submitted.
If you were making a purchase, you should click Cancel to
avoid a duplicate transaction. Otherwise, click Retry to display
the webpage again.
But the PRG pattern helps avoid this altogether by sending the client a redirect message so when the page finally appears, the last request the browser executed was a GET request for the new resource.
Here's a great article on PRG that provides an implementation of the pattern for MVC. It's important to note that you only want to resort to a redirect when an non-idempotent action is performed on the server. In other words, if you have a valid model and have actually persisted the data in some way, then it's important to ensure the request isn't accidentally submitted twice. But if the model is invalid, the current page and model should be returned so the user can make any necessary modifications.
Here's an example Controller:
[HttpGet]
public ActionResult Edit(int id) {
var model = new EditModel();
//...
return View(model);
}
[HttpPost]
public ActionResult Edit(EditModel model) {
if (ModelState.IsValid) {
product = repository.SaveOrUpdate(model);
return RedirectToAction("Details", new { id = product.Id });
}
return View(model);
}
[HttpGet]
public ActionResult Details(int id) {
var model = new DetailModel();
//...
return View(model);
}

While serving up the order confirmation page you can set a token that you also store in the DB/Cache. At the first instance of order confirmation, check for this token's existence and clear the token. If implemented with thread safety, you will not be able to submit the order twice.
This is just one of the many approaches possible.

Note that the PRG pattern does not completely guard against multiple form submissions, as multiple post requests can be fired off even before a single redirect has taken place - this can lead to your form submissions not being idempotent.
Do take note of the answer that has been provided here, which provides a workaround to this issue, which I quote here for convenience:
If you make use of a hidden anti-forgery token in your form (as you
should), you can cache the anti-forgery token on first submit and
remove the token from cache if required, or expire the cached entry
after set amount of time.
You will then be able to check with each request against the cache
whether the specific form has been submitted and reject it if it has.
You don't need to generate your own GUID as this is already being done
when generating the anti-forgery token.

Give each visitor's form a unique ID when the page is first loaded. Note the ID when the form is submitted. Once a form has been submitted with that ID, don't allow any further requests using it. If they click refresh, the same ID will be sent.

Simply do a redirect from the page that does all the nasty stuff to the "Thank you for your order" page. Having done that, the user can hit refresh as many times as he likes.

If you doesn't like redirect the user to other page, then by using my way you dose not need Post/Redirect/Get (PRG) Pattern and the user remain on the current page without fear of the negative effects of re-submitting of the form!
I use a TempData item and a Hidden field (a property in the ViewModel of the form) to keep a same Guid in both sides (Server/Client) and it is my sign to detect if the form is Resubmitting by refresh or not.
Final face of the codes looks like very short and simple:
Action:
[HttpPost]
public virtual ActionResult Order(OrderViewModel vModel)
{
if (this.IsResubmit(vModel)) // << Check Resubmit
{
ViewBag.ErrorMsg = "Form is Resubmitting";
}
else
{
// .... Post codes here without any changes...
}
this.PreventResubmit(vModel);// << Fill TempData & ViewModel PreventResubmit Property
return View(vModel)
}
In View:
#if (!string.IsNullOrEmpty(ViewBag.ErrorMsg))
{
<div>ViewBag.ErrorMsg</div>
}
#using (Html.BeginForm(...)){
#Html.HiddenFor(x=>x.PreventResubmit) // << Put this Hidden Field in the form
// Others codes of the form without any changes
}
In View Model:
public class OrderViewModel: NoResubmitAbstract // << Inherit from NoResubmitAbstract
{
// Without any changes!
}
What do you think?
I make it simple by writing 2 class:
NoResubmitAbstract abstract class
ControllerExtentions static class (An Extension class for System.Web.Mvc.ControllerBase)
ControllerExtentions:
public static class ControllerExtentions
{
[NonAction]
public static bool IsResubmit (this System.Web.Mvc.ControllerBase controller, NoResubmitAbstract vModel)
{
return (Guid)controller.TempData["PreventResubmit"]!= vModel.PreventResubmit;
}
[NonAction]
public static void PreventResubmit(this System.Web.Mvc.ControllerBase controller, params NoResubmitAbstract[] vModels)
{
var preventResubmitGuid = Guid.NewGuid();
controller.TempData["PreventResubmit"] = preventResubmitGuid ;
foreach (var vm in vModels)
{
vm.SetPreventResubmit(preventResubmitGuid);
}
}
}
NoResubmitAbstract:
public abstract class NoResubmitAbstract
{
public Guid PreventResubmit { get; set; }
public void SetPreventResubmit(Guid prs)
{
PreventResubmit = prs;
}
}
Just put them in your MVC project and run it... ;)

Off the top of my head, generate a System.Guid in a hidden field on the GET request of the page and associate it with your checkout/payment. Simply check for it and display a message saying 'Payment already processed.' or such.

Kazi Manzur Rashid wrote about this (together with other asp.net mvc best-practices). He suggests using two filters to handle data transfer between the POST and the follwing GET using TempData.