Can I use Npgsql Data Provider in my .NET 4.0 project? - postgresql

I have an MVC project that I would like to write in .NET 4.0
Is it possible to use Npgsql (which currently supports .net 3.5 ) if I will use it through Entity Framework, and I will limit myself to features of EF contained within 3.5?

Npgsql now supports .net 4.0 :D so question is no longer valid.

Related

How to use EF Core 6.0 with an application that uses .Net Framework?

I have a situation where an application uses various component libraries. The libraries were based on .NetStandard2.0/2.1 and internally used EF Core 3.1. For various deployment and development reasons, we now want to target EF Core 6.0, which raises the following issues.
Net Core 3.1 support runs out in December 2022 so we need to move away from it.
The application uses Net Framework functionality and cannot move to Net Core.
EF Core 6.0 does not support NetStandard, only Net 6.
Changing the library that uses EF Core to target NET 6 means that components referencing it also need to reference Net 6.
Dependencies trickle down to the application that targets Net Framework and, as a result, the application no longer builds because Net Framework is not compatible Net 6.
How can the Net Framework application use the Net 6 assembly? Or, more specifically, how can a Net Framework application use libraries that internally use EF Core 6.0?
The interface between the application (Net Framework) and the one single touch point library component (Netstandard) is very well defined. Maybe Pinvoke could solve the problem? Or something simpler that I have overlooked?
Somewhat related question: NU1202 Package Microsoft.EntityFrameworkCore 6.0.3 is not compatible with netstandard2.1
Other than process to process communication between .NET Framework and .NET 6, this is not supported (for example via a Web API or similar)
As a short term solution, you can change your .Net Standard 2.0 EF Core libraries to be multi targeted to both .Net Standard 2.0 (which will reference EF Core 3.1) and .Net 6 (which will reference EF Core 6). This will let your .Net Core apps use EF Core 6, while allowing your .Net Framework apps to use the same dlls, but to be using EF Core 3.1. I realize that EF Core 3.1 support ends December 2022, but it will keep things moving.
https://learn.microsoft.com/en-us/nuget/create-packages/multiple-target-frameworks-project-file
Btw, has Microsoft even attempted to address the fact that a .Net Framework application cannot reference .Net 6, therefore it cannot use EF Core 6? This is a major issue for us, as we were sold the idea that .Net Standard could be shared between .Net Framework and .Net Core, but this has ceased to be the case since .Net Standard 2.1 was introduced, and now MS has pushed all new features, like EF Core, to .Net 6.

Do I have to use npgsql for a project on prosgresql, EF Core and .net Core

I am starting a project with prosgresql, EF Core and .net Core. For this case is it a must to use npgsql?
It isnt a must to use npgsql you can use EF Core on its own https://www.npgsql.org/efcore/index.html.
However I would recommend using npgsql apposed to EFCORE, I use it for when working with .NET CORE and PostgresSQL they also have great documentation at https://www.npgsql.org/doc/basic-usage.html and you don't need to depend on EF

Can Entity Framework 6 be used in a .NET Standard project?

And if not, will it be? If so, when?
I haven't been able to find any clear official information on this, and the limited information I was able to find on Stack Overflow is a year or two old.
I was able to find official information saying EF 6.3 will be able to be used in a .NET Core project, but I couldn't find a release date for it, nor am I sure what the implications for use in a .NET Standard project are.
EF 6 supports .NET Standard 2.1, which is currently supported by .NET Core 3.0 or later - no .NET Framework version. EF 6 also supports .NET 4.0 and 4.5 or later.
https://github.com/aspnet/EntityFramework6/blob/release/6.4/src/EntityFramework/EntityFramework.csproj#L6
Some clarification, since EntityFramework 6.3.0 .NET Standard 2.1 has been supported. However there is no .NET Framework version that supports .NET Standard 2.1. Comment from Microsoft:
NET Framework won't support .NET Standard 2.1 or later versions. For
more details, see the announcement of .NET Standard 2.1.
This means that a majority of all applications using EntityFramework 6.X won't be able to use the .NET Standard 2.1 project anyway.
https://learn.microsoft.com/en-us/dotnet/standard/net-standard
https://www.nuget.org/packages/EntityFramework/#

Where is Entity Framework in Visual Studio 2017?

I've verified that Entity Framework 6 Tools is installed as suggested in other answers on this site, but ADO.NET Entity Data Model never shows up in the New Items/Data list. I've also tried installing the .NET CORE 2.0 SDK as other answers have suggested to no avail.
To be clear, I'm not creating a .NET CORE application, I'm just trying to make a class library based on .NET framework 4.6. I created the project via .NET Standard and selected Class Library (.NET Standard).
I just need to install EF so I can do a code first generation from my existing SQL Server DB.
Don't use .NET Standard, select a .NET Framework project type.
.NET Standard is an abstract "Core or Framework" option, as if the naming wasn't confusing enough.

Where is the "System.Composition.TypedParts.dll"?

I am trying to use the ContainerConfiguration type from the Managed Extensibility Framework (MEF). According to here, it lives in "System.Composition.TypedParts.dll" which is part of .NET Framework 4.5. But I cannot find it in Add Reference for a .NET 4.5 application.
Where can I find this DLL?
It turned out to be part of MEF 2, which needs to be installed with NuGet. It's not distributed with .NET Framework.