I have a web solution that contains 5 class libraries and one asp.net web site project. It's an e-commerce solution that is compiled for .NET 3.5 (some class libraries are set to .NET 2).
When I got VS 2010 installed I decided to give a try and upgrading it to .NET 4 but that didn't go so well, can't remember why. I reverted the source code control, cleared all local files, re-downloaded from source control and went back to VS 2008.
I decided to give it another try with VS 2010 due to some issues with VS 2008 but when I build the solution it fails because one of the class libraries is compiling to .NET 4. I checked the project settings and it is set to .NET 2. I have tried doing a clean on the solution, that makes no difference, the project always builds the assembly to .net framework 4.x.
I imagine something is getting cached on the system, i.e. msbuild, etc. Does anyone know where to clear this cache so that whatever is holding my class library hostage to .net 4 can actually let it completely recompile and pick up the project settings again?
Thank you.
This was a problem in the project file having the Tools attribute set which just needed to be cleared for .NET 4 compilation.
Related
I'm confused. We upgraded our project recently to .NET 4.5.1. We installed .NET 4.5.1 on our servers.
I'm referencing assembly System.Threading.Tasks.Dataflow from the GAC at C:\windows\Microsoft.Net\assembly\GAC_MSIL\System.Threading.Tasks.Dataflow\v4.0_4.5.9.0__b03f5f7f11d50a3a\System.Threading.Tasks.Dataflow.dll
CopyLocal is set to false as (I assume) it's part of the Framework, so should be already installed wherever the app is deployed.
The trouble is, when running on the server, it says it can't find this assembly.
I've read here that is is part of .NET Framework 4.5:
but the library is now built-in with .NET 4.5.
...and I've read here that it isn't!
The TPL Dataflow Library (System.Threading.Tasks.Dataflow namespace) is not distributed with the .NET Framework 4.5
What gives? It doesn't look like it is. Is it just part of the 'targetting pack'? Is it me, or are these in-place upgrades more agro than they're worth?!
I'm not sure why that page says it is part of .NET 4.5 -- it's still an out-of-band NuGet release, like Entity Framework, MVC, etc.
I recognize this question is pretty old, but I wanted to add my solution as well. I found adding the below two items to the Visual Studio 2019 install (run Visual Studio Installer > Modify > .Net Desktop Development) the problem went away and it was able to pull System.Threading.Tasks.Dataflow from the GAC.
Edit: Installing Visual Studio 2015 also seemed to be required. Obviously it isn't VS 2015 itself, just something it comes with. But there are too many packages for me to figure out which one easily.
Edit2: This isn't really the best solution, more of a stopgap. MS suggests downloading it through Nuget. https://learn.microsoft.com/en-us/dotnet/api/system.threading.tasks.dataflow?view=netcore-3.1
The TPL Dataflow Library (the System.Threading.Tasks.Dataflow namespace) is not distributed with .NET. To install the System.Threading.Tasks.Dataflow namespace in Visual Studio, open your project, choose Manage NuGet Packages from the Project menu...
Is there any trick/workaround/known "gotcha" regarding Entity Framework 4 and Visual Studio 2012?
I have a project that works and compiles perfectly on my Windows 7, VS 2010, .NET 4 box. Over the weekend I setup a new machine, with Windows 8 Enterprise RTM, and VS 2012 Ultimate RTM. EF design is out of the box, using ObjectContext approach (pre EF 4.1).
I retrieved the working solution from source control, went through conversion process, and get it to build successfully in VS2012 targeting the .NET 4 Framework.
However, when I run the app or debug it, I get "unable to load metadata resource" from the first EF call. Soo ..
Step 1: Work the EF error
Ok, so I use dotPeek to see the assembly, and sure enough when built in VS2012, the EDMX metadata files are not in the assembly.
Step 2: work the missing resources problem
I set metadata processing to "copy to output" and then back to "embed" to force. Nope.
I looked around the MSBUILD files for 4.5 to see if the EntityDeploy targets looked corrupt. Nope.
I did a full repair on VS 2012 to see if something got messed up. Nope.
Set MSBUILD VS version to "11.0" to avoid the 2010 compatibility checks in the csproj. Nope.
Step 3: Delete model, try again using VS 2012 defaults
Ok, I figured I just couldnt make this work. So I deleted the model, and readded as new in VS 2012, which uses EF 5.0 from NuGet, and recontructs using the DbContext approach. Got all this lined up, fixed a few syntax things b/t EF 4.0 and 5.0 and we are building.
Still get same error, still no resources in .DLL
A collegue of mine can build this successful in VS 2012 but on Windows 7 w/o .NET 4.5 installed.
Is there a bug or known issue in .NET 4.5 or MSBUILD 4.5? gotta be missing someting simple.
Figured it out. I don't have a .resources file in this project and it appears CoreCompile in .NET 4.5 is not embedding any of the EF resources files without that being present.
Trying to research is this is expected or new behavior.
I have a Visual Studio 2010 Solution with a class library project. What I want to do is compile 2 DLLs on build. I want to compile against .NET 3.5 and .NET 4.0 respectively. Something like below.
myproject\bin\debug\3.5\assembly.dll
myproject\bin\debug\4.0\assembly.dll
Is this possible?
Maybe you'can write a simple problem to execute on each build, it simply does:
make a copy of your working project file (*.csproj, *.vbproj, etc.)
edit the target info from 4.0 to 3.5 (or from 3.5 to 4.0) and update other related properties, it should be simple enough.
call msbuild.
I've used this approach before for different purpose.
The target framework is part of the application project settings that cannot depend on the configuration (unlike build settings).
I'm afraid you will have to create a separate project for each framework version.
Here's a puzzler - something that doesn't work that I assumed would (no surprise there).
We have a library project that is referenced in a few other desktop app projects. The library project is written in VS 2005 (.NET 2.0).
My problem is that some of our apps still live in VS 2005 for the time being (for various reason). I can't seem to reference this library project in VS 2010 without it demanding that I upgrade it to .NET 4, which if I do, then breaks my ability to include it as a reference in my VS 2005 projects.
This type of thing fries my brain. Is there any way I can make this work?
Hmm, that doesn't make a lot of sense. You don't reference a 'library project', you reference the DLL that it produces. Project + Add Reference, Browse tab. There's no known problem with that, within a 95% accuracy guess, mixed mode assemblies have a few hairs.
If you actually try to load a vs2005 project into a vs2010 solution, then yes, it's going to try to convert the project file. And that turns vs2005 catatonic, it doesn't have the time machine to guess what a vs2010 project looks like. Just making a copy of the project directory solves that problem.
Can you change the .NET version back to 3.5 or 2.0 in VS.NET 2010 after it revises the project version to .NET 4.0?
Use a file reference to the built dll, rather than a project reference.
You may also find you need to add an extra bit of compatible-framework info to your manifest file to tell .net to allow your .exe to use .net 4 and .net 2 assemblies alongside each other - if it's not there you'll just get an error on startup. (Sorry, I can't remember the exact details and I'm not at my work machine right now to be able to find them - but if you have problems at runtime, the error message should lead you to the exact solution you need)
Correction: I was thinking of this 'useLegacy' startup setting, which you may need to add to your app.config if you want to use a mixture of .net 2.0 and .net 4.0 assemblies in your application:
<startup useLegacyV2RuntimeActivationPolicy="true">
<supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
</startup>
On option, that is a complete PITA, but should work is:
Create a new project file in 2010 that includes everything the 2005 project file has. Just call it MyProject2010.csproj or whatever.
Then, add this project to your 2010 solution.
When I change the target framework of any project in Visual Studio 2010 it does not actually change the System assembly references. For example if I target v2.0 and check the properties of System and System.Data I can see that they are still both v4.0. If i change the target to v3.5, System stays at v4.0 but System.Core changes to v3.5.
Because of this I am truly not targeting anything except v4.0.
There may be something strange in your install. I just created a WPF project, keeping the default settings, thus targeting .NET 4. Then, I switched to 3.5. VS asked to reload the project and then the targeted runtime of the references was v2 (correct) and their version was 3.5 (with an error that Microsoft.CSharp and System.Xaml were missing, which is understandable).
Then, I did the same for .NET 3 and 2 and got the same results: after reloading the project, the version of the referenced DLLs had changed were it made sense (System.Data is always v2.0).
When using the CLR v2, the vshost debug helper had its name changed to something like vshost-clrv2.
I've reinstalled Visual Studio several times and it hasn't solved anything. After uninstalling there is 10.0 stuff laying all over the place leading me to believe the uninstaller is also leaving what ever is causing this issue. I'm going to have to reinstall the OS to get the issue to go away.
I also wanted to link to my earlier post because this post has more information about how I originally discovered this issue, contains a link to the Microsoft Connect bug report I opened and links to several other users experiencing the same problem: Visual Studio 2010 Can no longer build .NET v3.5