I thought I'd try using EF 5 with C++/CLI in VS2012, so that I could try Code First. The package downloads via NuGet fine, but isn't visible to the solution.
On investigating, the Package Manager says that the package is not compatible with the version of the Framework being used by the solution, and requires 4.0 or 4.5... but the config for the project (a plain Win32 console app) says it is using v4.5.
Has anyone come across this and found a way to fix it?
Related
tl;dr:
I have a .NET Framework 4.7.2 project consuming a NuGet package which supports .NET Standard 2.0. That package, in turn, requires another package which supports .NET Standard 2.0. However, when run, the latter package uses net461 binaries rather than netstandard2.0.
How do I force a NuGet package & its dependencies to use .NET Standard 2.0?
Are there special steps required to consume a .NET Standard package from a .NET Framework 4.7.2 project?
Specifics:
I am trying to get the NuGet package for SparkplugNet (which uses the MQTTNet package) working in a .NET Framework 4.7.2 project - just the basic "How to use" SparkplugB example. Both projects support .NET Standard 2.0. After some debugging (details below), it appears MQTTNet is trying to use code paths specific to .NET Framework 4.6.1, rather than .NET Standard 2.0, and crashing with no feedback whatsoever.
To troubleshoot, I built SparkplugNet and MQTTNet from source. As far as I can tell, the crash comes from hitting .NET 4.5/4.6.1-specific code in CrossPlatformSocket.ConnectAsync(), specifically this line (in context):
await Task.Factory.FromAsync(_socket.BeginConnect, _socket.EndConnect, host, port, null).ConfigureAwait(false)
When I debug, _socket is a System.Net.Sockets.Socket which doesn't appears to have a BeginConnect() method, at least in the source file my debugger pulled. I am not sure why it branches to that code when .NET Standard 2.0 would be a better fit.
Back to a 4.7.2 project consuming SparkplugNet & MQTTNet via NuGet package.... If I look at the reference paths, SparkplugNet is properly pointed at the netstandard2.0 folder, but MQTTNet points to packages\MQTTnet.4.1.3.436\lib\net461\MQTTnet.dll. If I change the hint path manually in the project file, MSBuild appears to pull from the netstandard2.0 folder, but it still crashes. I assume it is the same cause, though I'm having trouble debugging using NuGet packages. Also, I'm hoping for a better solution than hacking hint paths.
Does Microsoft EntityFrameworkCore work with standard .Net Framework applications?
I read a couple posts which said it was possible to.
However, when attempting to install via NuGet Package Manager, I get the following error message:
Could not install package "Microsoft.EntityFrameworkCore.Design
5.0.0". You are trying to install this package into a project that targets ".NetFramework, Version=v4.7.2', but the package does not
contain any assembly references or content files that are compatible
with that framework.
Is there something I'm doing wrong, or is EntityFrameworkCore not intended for use with standard .NetFramework applications?
Sorry, I have to correct my answer, I was wrong. EF Core 3.1 can be used with .NET Framework 4.7.2 or later.
EF Core 5.0 cannot be used with .NET Framework 4.7.2
see https://learn.microsoft.com/en-ca/ef/core/miscellaneous/platforms
I also tried it before and got the same error message described above
As soon as I've solved one issue with IBM.EntityFrameworkCore, another one has arose. Everything is soooo hard and painful with DB2 and their .NET team...
The problem: I have several EntityFrameworkCore - based projects in the same VS solution, for example MyDb2EfModel, MyMsSqlEfModel, and MyNpgsqlEfModel. (It's kind of a complex data-integration scenario.) On top of that I have a CLI project which references all the three and performs actual data ops. When the CLI project references only MyDb2EfModel project - IBM.EntityFrameworkCore works as expected. But as soon as I add references to the remaining two projects - it simply stops working and throws some misleading exception. The exception happens because overridden DbContext.OnConfiguring and DbContext.OnModelCreating methods aren't called anymore. When there's only one reference (MyDb2EfModel) the methods get called as expected, and everything works. But with all three library projects referenced - they aren't called anymore.
Let's also note that the mentioned methods get called on DbContext instances from MyMsSqlEfModel and MyNpgsqlEfModel libraries. The only one that stops working is MyDb2EfModel (which is based on IBM.EntityFrameworkCore).
Thumbs down for IBM and their .NET team! It's ridiculous how these guys are making things be 100 times more complicated then with any other DB.
The question is obvious: Does anyone has any experience in a similar scenario, and hopefully any suggestion how to resolve the issue?
Thanks!
I've found the reason. It turned out that it's about Microsoft.EntityFrameworkCore version. Currently available version of IBM.EntityFrameworkCore is 1.1.1.101 (.NET Standard 1.6), and it uses Microsoft.EntityFrameworkCore version 1.1.1 or 1.1.2. It cannot be used with Microsoft.EntityFrameworkCore version 2.0.0 (.NET Standard 2.0) - it throws the exception I was getting.
In the other two libraries I've used Npgsql.EntityFrameworkCore.PostgreSQL version 2.0.0 and Microsoft.EntityFrameworkCore.SqlServer version 2.0.0, both depending on Microsoft.EntityFrameworkCore version 2.0.0 (all in .NET Standard 2.0).
So when I referenced only MyDb2EfModel in my CLI project everything was working because only Microsoft.EntityFrameworkCore version 1.1.2 is referenced and used. But as soon as I add reference to another projects CLI ends up with dependencies on both Microsoft.EntityFrameworkCore version 1.1.2 and 2.0.0 versions, and the newer (2.0.0) is loaded and used. And IBM.EntityFrameworkCore was failing because it cannot use it.
How to solve? Either wait for IBM.EntityFrameworkCore for .NET Standard 2.0, or downgrade other references to ensure that Microsoft.EntityFrameworkCore version 2.0.0 isn't used anywhere (which will cause other headaches).
So although it's not about a bug in IBM.EntityFrameworkCore, IBM DB2 .NET team is still to blame for not having .NET Standard 2.0 at least preview published, although .NET Standard 2.0 is available for almost a year now, recently reaching its "release" version. And there are more things to blame IBM DB2 .NET team for (unrelated to this particular issue).
This scenario goes a bit against the whole way nuget works so what i might be asking for is a hack...
My problem:
I need to have Restsharp and Protobuf-net referred to in a .net assembly that going into SQL-CLR for Server 2008 (so max .net 3.5, framework 2.0).
Restsharp goes back to 3.5 as the lowest supported fwk version.
Protobuf-net 3.5 onwards has a lot of gunk referring to system.servicemodel (and WCF) which i don't need and use and actively want to remove because it causes issues with installing on SQL-CLR. Protobuf-net 2.0 doesn't have this :)
So i've built and tested my code with an assembly targeting .net 3.5 and i installed the restsharp nuget - which gave me the correct reference and i manually added a reference to the protobuf-net 2.0 distro.
This is where i'd like to know - can i (in any way) install the protobuf-net nuget package but still have it reference the .net20 DLL in my assembly which targets 3.5?
The static reference is not a huge deal since protobuf-net has been pretty stable, but i'd like to get the whole setup via nuget if possible.
In the end, this is a workaround as solution to:
protobuf-net version without system.servicemodel dependency?
If there's a better answer to that, i'd be very grateful :)
As far as I know, that is not possible. You could of course create your own custom build and host it on a local nuget drop, or as your own nuget package on the public feed. AFAIK, there's no way to do what you want inside a new nuget folder in the existing package.
I am using VS2010 with SP1 (also have VS2012 installed on the same machine). Moles 1.0
The project is using .NET 4
I added moles assembly to system.dll and get the following error on compile
Error 46 The type or namespace name 'IReadOnlyList' does not exist in the namespace 'System.Collections.Generic' (are you missing an assembly reference?) [C:\Test\obj\Debug\Moles\s\m.g.csproj] C:\Test\m.g.cs Test
IReadOnlyList .NET 4.5 as far as I know.
Anyone else got this issue?
Updated Solution
I was able to get Pex to run in VS 2010 with .Net Framework 4.5 installed. Maybe others have explained that this is the solution but my issue (being new to Moles and Pex) is that many of the explanations were vague. Thanks to the author of these posts because they got me headed in the right direction:
http://feherzsolt.wordpress.com/2013/02/13/moles-and-net-4-5/
http://www.daedtech.com/using-moles-with-the-system-assembly
So the solution is to create a new .moles file (System.moles) in the test project at the same level that Pex created the yourAssemblyUnderTest.moles file and add the following to the file.
<Moles xmlns="http://schemas.microsoft.com/moles/2010/">
<Assembly Name="System" ReflectionOnly="true" />
</Moles>
You may have to clean (or manually delete the obj folder contents) and rebuild but this solution worked for me. I also noticed that the first build would report build errors, but the errors would go away on subsequent builds.
Alternative Solution
I know this isn't THE solution but it is a (poor) workaround that allows Pex to run...plus this was too long for a comment. If anyone knows how to get PEX to run on a machine with the 4.5 .Net Framework PLEASE respond.
This was my scenario. I have a machine with the .Net Framework 4.5 and I have Visual Studio 2010 and 2012 installed. I installed Pex (en_visual_studio_2010_pex_0.94.51023.0_power_tools_x64_598803.exe) and could run Pex in a VS 2010 project that was targeting .Net Framework 4.0. I could run Pex and it identified issues...but once I promoted issues to Unit Tests the unit test project wouldn't compile because of the following build error
The type or namespace name 'IReadOnlyList' does not exist in the namespace 'System.Collections.Generic' (are you missing an assembly reference?)
After much searching, and reading that Pex or Moles was replacing 4.5 .Net Framework assemblies with 4.0 versions I decided to uninstall 4.5, install 4.0, and give it a try. Running on 4.0 works just fine and I didn't need to define Mole type filters to get it to work. Then I tried tried to upgrade to the 4.5 Framework again...but sadly I end up right back where I started with the IReadOnlyList namespace issue.