View does not refresh after change

Question

I am having this frustrating problem. I change text in a razor view (cshtml), Start without Debugging, refresh (Ctrl+F5) the browser but nothing happens. The strange part is that if I modify a controller's return value (say return Ok("test");) or an included static file (like CSS), refresh, the change is visible. The razor view only updates if I stop start and stop debugging every time.

Here are things I have already tried:

• Made sure that Detect when file is changed outside the environment is checked.
• On run, when projects are out of date is Always build.
• Tried this on Edge, Chrome and Firefox with and without hard refreshing.
• Restarting Visual Studio numeral times.
• Cleaning/rebuilding solution.
• Doing this on new template projects.

P.S. I see there are many similar questions, none of the answers, however, seem to fix my problem.

Update

This appears to be a problem on a much larger scale. If I:

1. Create a required razor section in the parent view like this @RenderSection("css", required: true).
2. Not implement the rendering in the child view.
3. I (obviously) get the InvalidOperationException: The following sections have been defined but have not been rendered by the page at 'bla\bla\bla':css.
4. Then I implement it.
5. Save, Ctrl+F5 in Firefox. The error persists.

At this point, VS 2015 is practically unusable because you don't know, if you're actually missing something or it's VS acting out

Peachy

Do you have caching turned on? – Ambulator

I have turned off caching in my browser(s) and always use Ctrl+F5 to force a clean reload, if that's what you mean. – Peachy

No, I'm talking about caching on the server. There are attributes on action methods, or you can probably use handlers to make the server hold onto the same response. – Ambulator

Can you show me a simple example? – Peachy

Answer 1

I had this problem before. My case was i run windows 10 VM Parallel on Macbook Pro, and the project files are in shared folder with mac OS.

Incase someone has the same case like me, move the project to non shared directory such as C:\ will fix the problem.

Condorcet

Running Win10 in Parallels on MacBook Pro. This fixed the problem for me. – Nape

My finding is that if you open a terminal-window, and change to the project directory and the use chmod to change rights, it will work. use: sudo chmod -R 777 * – Theadora

I am on Win10 Parallels on Mac and my project is in C:\ and I disabled sharing of projects between Mac and Windows, but it's still not working for me. – Forest

@Forest still working with me today, i'm still using mac for .net project with parallels – Condorcet

Answer 2

Here's what seems to be happening under the hood: the .net framework compiles your razor into a machine-form (DLL) and executes this. It then monitors your web folder to watch for changes, and when it detects changes, it re-compiles your razor and executes the new DLL.

In your case something seems to fail related to the monitoring file-changes. It still works on a full restart, because then compiling happens even without file-change detection. Common reasons are:

1. You're serving the files from the network (a NAS or file-share) which doesn't allow your pc to monitor changes. This can be a missing feature (like a non SMB file-share) or a permission issue. This is very common in web-farm scenarios, but probably not your dev-scenario.
2. Something else is already locking the files (permissions?) which prevents this monitoring hook to hold on to the files.

To confirm that this is the issue, I recommend just editing the web.config (add/remove a character) and see if then the reload is successful - just to prove it's a re-compile issue and not a visual-studio-debugging issue. Assuming this is the case, and assuming it's not a NAS, I would recommend to temporarily give the folder a "everyone - everything" permission to see if it works then, and then gradually reduce the permissions again to where you want them.

Typo

Answer 3

check your web.config and make sure you do not have fcnMode="Disabled" or fcnMode="NotSet"

use

<httpRuntime targetFramework="4.5.2" fcnMode="Default" />

or

<httpRuntime targetFramework="4.5.2" fcnMode="Single" />

• Default For each subdirectory, the application creates an object that monitors the subdirectory. This is the default behavior.
• Disabled File change notification is disabled.
• NotSet File change notification is not set, so the application creates an object that monitors each subdirectory. This is the default behavior.
• Single The application creates one object to monitor the main directory and uses this object to monitor each subdirectory.

FcnMode Enumeration

Couchant

Thanks for posting that - I can have my sanity back now!!! I ran into this issue with one of my MVC sites and it was driving me NUTS!! I noticed the fcnMode attribute. After some searching on DDG I came across your reply. I'm running Win10 in a Parallels Desktop VM using shared folders. The project I was running is located on a UNC path eg \\Mac\{DriveName}\... For anyone else running a similar environment - I had to change this to "Default" for it to work properly - even then I have to save the view a few times. – Entrechat

im sorry but where do I put this code in web.config?? <httpRuntime targetFramework="4.5.2" fcnMode="Single"/> – Intoxicant

put it inside <system.web> </system.web> – Couchant

I too run Win10 in Parallels, but this didn't fix the problem for me. @dexcell provided an answer above that did, however. – Nape

Why do you say that NotSet and Default are both the default behavior? If I don’t have the attribute set at all, does that mean it shouldn’t work for me? But it did when I never had this attribute in my web.config before… – Prelatism

@Prelatism that was copied from Microsoft docs learn.microsoft.com/en-us/dotnet/api/… – Couchant

@Moes Please use a quote block to make it clearer that you’re copying from the docs verbatim: stackoverflow.com/help/referencing – Prelatism

Also, it appears that Default is the actual default. So there’s no point in ever saying fcnMode="Default" unless you have a complex configuration with inherited values where an inherited configuration specified something other than fcnMode="Default". – Prelatism

Answer 4

On Parallel virtual machines, on the Macbook Pro, if the project files are in shared folders, the recompilation mechanism will not work; Copy the folder to drive C and the problem will be solved

Pulse

I spent quite some time to figure this out... Thanks! – Terrier

Answer 5

If you're running on Mac using a Parallels WM and you project is located on you Mac-volume, you can solve this with using chmod.

chmod -R 777 *

Theadora

WARNING: trying this solution caused huge problems with git showing changes to every file. DO NOT TRY THIS IT IS A TERRIBLE SOLUTION. – Icono

This was my issue, I chose to move the folder into the logical Parallels VM drive rather than change permissions - certainly fixed it and I would not have worked it out without this answer – Enviable

@Icono Not, if you're using git in Windows.. works fine for me. – Theadora

Answer 6

Just had the same issue. After debugging for a long time and trying almost everything we found out that someone had moved the file from one folder to another in Visual Studio and checked that in to TFS. So the project file was updated but the original file still existed on disk. So my local IIS rendered the old file and not the new file on the new location.

This was frustrating, yes.

Argile

Answer 7

There are two ways to resolve this issue:

1. Check the permissions of folder in which your .sln file present.There may be a problem with file access permissions as Visual studio may not be to access files when IIS express server is running, so to reflect new .cshtml changes each time you need to restart the server,so I suggest edit the folder access permissions by:

Right click on folder->properties->security->click on edit button -> check all options->save.

Restart Visual studio to see changes.

If this does not work then use 2 option.

2.In your project in startup.cs file add this below line ConfigureServices() in method :

services.AddMvc().AddRazorOptions(options => options.AllowRecompilingViewsOnFileChange = true);

Highbred

@Ashu, this answer is for .net Core (2.2+). Not sure if that still merits a downvote, since the OP's question was pretty broad (even the tags are somewhat ambiguous wrt to .net Core (Core can be implemented with the C# lang and has an MVC package)). – Debauchee

this answer worked for me on asp.net core 2.2 and 3.1 for razor pages (the other solution is for MVC site and Mac running Parallel). – Dillard

I got it. actually i was on the latest version and not able to find that function but after research realized that it exits in other versions. tried to up vote it again but getting error that answer must be edited once now. – Nearby

For Razor Pages, the method described at learn.microsoft.com/en-us/aspnet/core/mvc/views/… works better – Dillard

Answer 8

Thanks to an answer to this question, about file permissions, I realized that the Windows "Temp" folder located in C:\Users\username\AppData\Local, did not have my user with permissions, it only had administrator and "everyone", I had to manually add my user and give it all permissions on the "Temp" folder. Before that, I cleaned my Temp folder (as much as possible) and in the project I cleaned the .vs, bin and obj folder. I opened the project again and it worked for me.

Tested on VS2022

Neoclassicism