I can easily create a vNext class library that compiles the source to .NET 4.5 and ASP.NET Core. I can also create a target for PCL (net40+sl50+wp80+win+wpa81+MonoAndroid10+MonoTouch10). The problem is that I would like my library to also target 3.5 but adding net35 to the "frameworks" list adds an entry in the references but expanding that shows that it actually imports .NET 4.5 assemblies so the compiled result is not targeting .NET 3.5 but instead 4.5...
Is is possible for the vNext class library to target .NET 3.5?
The references displayed on VS2015 show indeed a link to .NET 4
But the generated NuGet shows 3.5 :
However I was not able to test of this really works when running on Windows with only 3.5 installed.
Related
In one of my .NET Framework projects, I introduced a new .NET Standard 2.0 project. This project has dependencies on some existing .NET Framework projects. I was wondering if this is right to do.?
The reason I added a .NETStandard project is that we have plans to move the whole repository to .NET Core / Standard. Hence I thought, the new project we add can target .NET Standard. With .NET Standard project I get the new SDK style project file, package references, etc by default.
The consuming application is still .NET Framework.
Do I have to retarget the new project to .NET Framework 4.7.2 so that the project will have the above SDK style project file and package references but targets .NET Framework 4.7.2 now. It will then be as easy as changing the target framework when we move to .NET Core?
Depends on your purpose of introducing the Standard 2.0 project. Normally, you make a Standard when you need it to be accessible both from .NET Framework and Core. In your case, your Standard project won't be operable from Core under macOS or Linux.
Yes, this can be done.
https://learn.microsoft.com/en-us/dotnet/standard/net-standard?tabs=net-standard-2-0
.NET Framework compatibility mode
Starting with .NET Standard 2.0, the .NET Framework compatibility mode was introduced. This compatibility mode allows .NET Standard projects to reference .NET Framework libraries as if they were compiled for .NET Standard. Referencing .NET Framework libraries doesn't work for all projects, such as libraries that use Windows Presentation Foundation (WPF) APIs.
This is necessary as an intermediate step for some projects, but in order to get to your final goal you will of course have to go all in on .net core which will require updating those projects not to use framework or they will crash at runtime.
I'm porting my WPF application from .NET Framework to .NET Core 3. I got this generic UI library that is published on NuGet, that is currently targeting .NET Framework v4.6.1. Now, if I just change the target to .NET Core 3, then it won't work anymore in .NET Framework projects. .NET Standard is designed to solve this kind of problem but I don't think it will help in the case of WPF projects.
What's the right thing to do here? Publish and manage 2 separate packages?
Then this library has 2 other derived libraries. If I create 2 separate packages for the base library, that means I'd have to publish and manage 2 of each derived libraries as well. This solution stinks. Got anything better?
A WPF application that targets .NET Core 3 may actually reference and consume a control library or NuGet package that targets .NET Framework 4.6.1.
You shouldn't have to do anything with the control library itself for this to work, assuming you don't use any APIs that is not present in .NET Core because then you will eventually get runtime errors.
Try to add a reference to the DLL or install the NuGet package as usual. It should work even if the NuGet package only contains a single assembly in lib\net461.
I've got a strange issue referencing a net standard application (FW Full 4.5.2)
I got this error targets 'netstandard2.0'. It cannot be referenced by a project that targets '.NETFramework,Version=v4.5.2'., wasn't .NET standard supposed to allow references from Core and Framework projects as well?
As stated here .NET implementation support. You need atleast .NET Framework 4.61 for referencing .NET Standard 2.0 assemblies.
My DLL is created using the .NET Standard 1.6 and ASP.net is using .NET Framework 4+
This is the Error that I am getting
Severity Code Description Project File Line Suppression State
Error Project targets '.NETStandard,Version=v1.6'. It cannot be
referenced by a project that targets
'.NETFramework,Version=v4.5.2'. WebApplication
Is there a work around for this ? Using the old ASP.NET framework instead of the new ASP.NET Core
I am not a fan of the Razor syntax, however I would like to use the old aspx syntax to create web forms.
Using : VS - 2017
Only .Net Framework 4.6.1 with tooling 2.0 supports .Net Standard 1.6. You will not be able to use DLL targeting .Net Standard 1.6 in application that's targeting .Net Full framework 4+ except 4.6.1 with tooling 2.0. Please refer this link for more details on platform support and compatibility.
It's like referencing a 4.5 assembly from a 4.0 project:
To see what .net standard version is implemented by what version of the .net framework, see: https://blogs.msdn.microsoft.com/dotnet/2016/09/26/introducing-net-standard/
I'd really like to start using .NET Core and slowly migrate applications and libraries to it. However, I can't realistically upgrade my entire code base to use .NET Core and then go through the process of testing and deploying a plethora of applications in production.
As an example, if I create a new .NET Core application and try to reference one of my .NET Framework projects I get the following:
The following projects are not supported as references: -
Foobar.NetFramework has target frameworks that are incompatible with
targets in current project Foobar.NetCore.
Foobar.NetCore: .NETCoreApp,Version=v1.0
Foobar.NetFramework: .NETFramework,Version=v4.5
Is it possible to create a new .NET Core application and reference my existing .NET Framework libraries? If so, what's the process for doing that? I've spent hours going through Microsoft's documentation and searching their issues on GitHub, but I can't find anything official on how to achieve this or what their long-term vision is for this process.
Old question, but with the release of .NetStandard 2.0 and .netcore 2.0 and vs2017.3, the game has changed.
You can use the Full .NET Framework (TFM) with .NetCore 2.0, but how?
In Visual Studio 2017.3, you can reference the Full .NET Framework (any version) directly from within a .NetCore2 project.
You can build the .NetStandard2 class library and reference your TFM. Then reference your .NetStandard2 library from your .NetCore2 project.
For example, referencing json.net net45 from .NetStandard2.
Browse to the folder and select version net45 (not netstandard1.3)
See the dependency in the image below, no yellow warning as you see.
Even if a Nuget library is not ready to be ported to .Netstandard 2, you can use any API in the library that is compliant to net461.
Quoting for the .NET Core 2/Standard 2.0 announcement with links:
.NET Core 2.0 is able to freely reference libraries that have been built for .NET Framework up to version 4.6.1
However, some libraries may fail at run time if they try to use API methods that aren't available on .NET Core
Reference: .NET Core App target .NET framework 4.5.2 on Linux
A need to use third-party .NET libraries or NuGet packages not available for .NET Core
So only in cases where the libraries or NuGet packages use technologies that aren't available in .NET Standard/.NET Core, you need to use the .NET Framework.
Reference: Choosing between .NET Core and .NET Framework for server apps
You can now reference .NET Framework libraries from .NET Standard libraries using Visual Studio 2017 15.3. This feature helps you migrate .NET Framework code to .NET Standard or .NET Core over time (start with binaries and then move to source). It is also useful in the case that the source code is no longer accessible or is lost for a .NET Framework library, enabling it to be still be used in new scenarios.
Reference: Announcing .NET Core 2.0
Yes, we are currently attempting the same thing. The trick is to make sure that you are supporting the same .NET frameworks. Inside your project.json file, make sure the framework matches the framework of the project you wish to include. For example:
"frameworks": {
"net46": { --This line here <<<<
"dependencies": {
"DomainModel": {
"target": "project"
},
"Models": {
"target": "project"
}
}
}
},
FYI: You might need to change the framework of your .NET Core or your older projects to achieve this. .NET Core can be changed just by editing the project.json file as seen above. You can so the same in .NET projects by right clicking the project and opening properties. Change the framework level there.
Once you have matched the two project frameworks then you should be able to include them. Good Luck!
We delayed migrations as long as could as it seemed daunting as first. But we got an insistent client who wanted to migrate ASAP.
So we migrated their Fintech Web App developed on .NET Framework 4.8 Web Forms to .NET 6 Razor Page. Our team scoured though hundreds of online resources & spoke to Microsoft Tech Support before we started the project. Hope the high-level walkthrough of our journey help you plan your migrations.
Our .NET Framework Website consisted of 1 .NET Web Forms project and 12 Class Libraries.
Here is how we did it.
Refactored the .NET Framework 4.8 Web Forms code
We ensured that the Web Forms code behind did not have a single line of service or business logic code. When we did find some business logic code in the web forms code behind, we refactored it, by moving it to the class libraries.
Created new .NET Standard projects
We created a new .Standard 2.0 Class library project for every .NET Framework 4.8 Class Library. If the original project was called "FintechProjectName.StockMarketClient", we named the .NET standard project "FintechProjectName.StockMarketClient.Standard".
Copied all files from .NET framework to .NET standard
We copied all the class files from .NET framework to .NET standard projects. We then removed all the .NET framework class libraries from the solution and added references to the new class libraries. All projects compiled on the 1st try itself and all our test cases too passed with minor changes.
Create new .NET 6 Web App Project
We created a new .NET 6 Web App Project. We had to entirely redo the front-end as there is no direct path for migrating Web Forms to Razor Pages. This was the only project which took us about 1 month to migrate.
Reference .NET standard class libraries in the new .NET 6 website
We copied all the .NET Standard libraries to this new solution containing the Razor Pages web site. Added the references and got it to work.
Move from .NET Standard to .NET 6 class libraries
Once the new website was up and running, with all test cases passed, we did the last step in the process which was the simplest. Created .NET 6 class library projects for each of the .NET standard libraries and named the projects appropriately. Copied all class files from .NET standard projects to their corresponding .NET 6 projects. Then we removed the .NET Standard libraries and added references to the new class libraries.
Overall project timelines were about a month and a half, most of it spend on Razor Pages implementation using the same html design.
Note:
If you are using any 3rd party library which does not have a .NET standard or .NET 5 version, then you are out of luck. You will need to find a replacement nuget package and recode your application to use this new library.
In my case with .net6 referencing framework 4.8 library ( both winforms), the trick seems to be to add the reference to the framework dll as a shared reference.