Are there any known stability issues when using .NET 1.1 libraries in a .NET 4.0 application?
We have used many .NET 1.0 libraries in different version of framework (any thing between 1.1 to 4.0) and have never experienced any issues. we currently use SQLDataProvider which I think was release a bit after .NET 1.0.
Then again it all depends on the code that is included in those libraries. I would spend some time to look for updated version of those libraries or even alternative, specially something that was written in 2.0 or higher just because of introduction of generics.
but otherwise, do some testing and you should be fine.
Generic answer is NO. You should be able to use .NET 1.1 libraries in a .NET 4.0 project witout any issues. But every library is different. Is it a custom dll? Does it use any COM components?
Related
I'm currently developing an application using .NET 5 and aim to migrate it to .NET 6 when fully released.
I'm considering using a library that's implemented in .NET Framework 4.5, which works in .NET 5
Will it still be compatible using .NET 6 & are there any other risks in using such a library in general?
Since your project is on .NET Framework 4.5 & is "working" in your .NET 5 project, it'll be targeting .NET Standard 1.0.
In that case, according to Microsoft documentation for .NET Standard versioning, .NET Standard 1.0 will be supported fully in .NET 6.0 as well.
You should have no issues moving forward with your upgrade.
Are there other risks?
It would be best to use a more updated library, which does the same functionality as the older library.
Of course, such a library may not exist hence why MSFT tries hard to maintain compatibility.
Other than the library not being able to take advantage of the latest .NET security & performance improvements that have been introduced with newer versions of .NET, you'll be fine.
I have a project that is targeted to .Net Framework 4.8. Now, we need to use a 3rd party dll. The problem is that the dll is targeted to .Net Standard 2.1.
Is there a way to use this dll in the .Net Framework 4.8 project?
I added the dll, get this error:
Could not load file or assembly 'netstandard, Version=2.1.0.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified.
I searched, seems it should work directly. Maybe I need to add a reference? Not sure what needs to do now.
Thanks
You cannot consume a .Net Standard 2.1 assembly in any .Net Framework Version because the .NET Framework (even the last ever version, 4.8) does not implement .Net Standard 2.1.
The .Net Standard .NET implementation support matrix at https://learn.microsoft.com/en-us/dotnet/standard/net-standard?tabs=net-standard-2-1 does not contain an entry for 2.1 under "Framework". Although very unlikely, the support matrix might change in time; this was the supported list at the time of writing.
More details on the decision by MS: https://devblogs.microsoft.com/dotnet/announcing-net-standard-2-1/
Extract:
Given many of the API additions in .NET Standard 2.1 require runtime
changes in order to be meaningful, .NET Framework 4.8 will remain on
.NET Standard 2.0 rather than implement .NET Standard 2.1. .NET Core
3.0 as well as upcoming versions of Xamarin, Mono, and Unity will be updated to implement .NET Standard 2.1.
Library authors who need to support .NET Framework customers should
stay on .NET Standard 2.0. In fact, most libraries should be able to
stay on .NET Standard 2.0, as the API additions are largely for
advanced scenarios. However, this doesn’t mean that library authors
cannot take advantage of these APIs even if they have to support .NET
Framework. In those cases, they can use multi-targeting to compile for
both .NET Standard 2.0 as well as .NET Standard 2.1. This allows
writing code that can expose more features or provide a more efficient
implementation on runtimes that support .NET Standard 2.1 while not
giving up on the bigger reach that .NET Standard 2.0 offers.
Solution:
The easiest way would be to convince the 3rd party to backport/multi-target to support netstandard2.0 as well. Alternatively, you can switch to targeting .Net 6 (LTS), .Net Core 3.1 (LTS), or Mono instead of Framework 4.8 in your project.
UPDATE:
Another possible workaround:
You might also attempt some trickery with .NET Framework compatibility mode. I had no idea you could do this. You could, for example, make a "wrapper" project that targets standard and references both your .Net Framework 4.8 code and the 3rd party library, unless the 4.8 part uses WPF - perhaps there are other pitfalls in unsupported scenarios as quoted below. It sounds convoluted to me, but if you have no other option, it might be worth a shot. From the same original site:
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.
(*) - Also .Net Core (elsewhere in the document/page)
This question already has answers here:
What is the difference between .NET Core and .NET Standard Class Library project types?
(13 answers)
Closed 3 years ago.
I want to create a library to use in .Net framework applications and Xamarin applications. But there are 3 framework versions:
.net core
.net framework
.net standart
So I could not decide which version to use my common library.
If I create a .net standart library, does it work in .net framework and .net core.
If I create a .net core library, does it work in .net framework and .net standart.
I am confused about frameworks.
This might help you decide
.Net Standard : Used for building libraries that can be referenced from all .NET implementations, such as .NET Framework, .NET Core and Xamarin
.Net Core : Used for building cross-platform console apps and ASP.NET Core Web apps and cloud services.
So when if you want your library to be supported by all different type of .Net implementations, .Net standard is the way to go.
As you're writing a C# library I imagine you know the difference between a class and an interface. A class is a concrete implementation of some feature set, and an interface defines what features you can expect from an instance that implements it.
Using this as an example, .NET Framework and .NET Core are like classes. .NET Framework is the "classic" implementation, and .NET Core is a newer implementation which has advantages such as being able to run on Linux. If you build a library to target .NET Core or .NET Framework, you are building it to target one of those concrete implementations.
.NET Standard on the other hand is like an interface. Each version of .NET Standard provides a set of features, and different versions of .NET Framework/.NET Core implement different versions of .NET Standard. When you build a library that targets a given version of .NET Standard, you're saying that you can support all of the concrete implementations in the corresponding column of that table.
Deciding what version of .NET Standard to target will depend on what functionality you need to implement your library. More features usually means a higher version and supporting fewer implementations. Fewer features means a lower version and more widespread support.
So many confusing other answers here.
First and foremost it depends on what platforms you are targeting.
is it a generic use library you want share with the world?
is it an application specific library (i.e. reusable code for the same application, i.e. a line of business application) which is to be used on multiple platforms
Case 1
You should go with .NET Standard, since it gives you the most platforms. Which version you use, depends on the features you need.
If you want reach the most platforms, try to target as low as possible (.NET Standard 1.0, it targets .NET Core 1.0, .NET Framework 4.5, Mono, Xamarin iOS 10/Mac 3.0/Android 7.0, UWP 10 and Uniy 2018.1 and all newer versions of these).
You can see the exact .NET Standard Matrix in the provided link.
If you need specific API you have to target a higher version, such as .NET Standard 2.0 which a lot (~22k new APIs from .NET Framework have been ported to .NET Core 2.0 from 1.1) APIs than .NET Standard 1.1.
This may not allow you all APIs (no WPF/WinForm specific apis) but in generic use reusable libraries this shouldn't be an issue.
Case 2
Here, you can also apply Case 1 tips, if possible.
If that doesn't cover your required Apis and you know you don't want target .NET Core or Unity, you can still use the old styled PCLs: Portable Class Library.
They are a more complicated versions of .NET Standard (kinda a predecessor of .NET Standard), where depending on which platform you target the API surface shrinks to only allow APIs to be used which run on all these platforms.
It's not recommended these days to use PCLs, since .NET Standard is preferred and more easy (for library authors) to use and target multiple platforms.
Last but not least, if you really need some feature only on Windows and .NET Framework (or you don't care for .NET Core), you can still cross-target, i.e. have a .NET Standard 2.0 for all platforms and add specific APIs only to net45 target and preprocessor instructions (#if NET45/#endif).
This compiles into two libraries, one for netstandard2.0 and one for net45 (.NET Framework 4.5).
I am writing a simple .NET 4.6.1 console application (not .NET core), as below
References are
The problem is, once compiled, it generates a hefty lot of dlls that are supposed to be build-in dlls. What is the problem?
You left a big clue in the screenshot.
They're recommending that libraries target .NET standard.
There's a good discussion at:
https://github.com/dotnet/standard/issues/146
Libraries should generally target .NET Standard as this ensures that
they can be consumed by any app. There will be circumstances where you
need to access .NET Core specific APIs, either because the API is new
and not implemented anywhere else, or the concept is .NET Core only.
That's why I believe we should make it easy to retarget between .NET
Standard and .NET Core so that developers never have to fear being
"locked in". Start with NET Standard and retarget if necessary &
revert back once a new version of the standard is available that has
all the APIs you need.
So gRPC now works with .NET Standard.
If you don't want to opt-in, you could build the particular library targeting the .NET Framework.
There is need to support legacy applications which are built in .net 1.1 framework. So i have interface assembly (ex. : ISample.dll version 1.4.0.0) also built in .net 1.1 framework, latest implementation of this interface assembly (ex. :Sample.dll 1.4.1.0) is built in .net 3.5 framework and policy redirection assembly( policy.1.4.Sample.dll) are also built in .net 3.5 framework.
I tried this it is not working. so question is, does .net framework support assembly redirection across different version 1.1, 3.5 or others ?
As far as I know a higher .NET version should support assemblies compiled for older .NET versions. The other way around could be a little bit complicated. You may follow the approach of CLR-hosting, by using the native CLR hosting interface of mscore and wrapping it backwards to your .NET1.1 application. But this still requires Version 3.5 installed on your system. For more information look here: http://msdn.microsoft.com/en-us/magazine/cc163567.aspx
But notice that this is really really inperformant and uncomfortable, because you have to wrap it back, and you have to wrap the used 3.5 assembly.
Otherwise I will have to say. "No there is no way (i know of) to do that."