将 EF（不是 EF 核心）应用到 ASP.NET 核心项目

Question

Goal:

Use Entity Framework (not EF Core) in an ASP.NET Core project.

According to instruction you have to create a .net project and then you go to ASP.NET Core project and add it to references by selecting this EF project. ( https://docs.microsoft.com/en-us/aspnet/core/data/entity-framework-6?view=aspnetcore-3.0#reference-full-framework-and-ef6-in-the-asp-net-core-project )

Problem: I get an error message

Error CS0012 The type 'DbSet<>' is defined in an assembly that is not referenced. You must add a reference to assembly 'EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'

I have already applied EF in the project but I still get this error.

I have also applied a github link that you can download the solution and its project
https://github.com/candyboyyy/ef

Info:
https://docs.microsoft.com/en-us/aspnet/core/data/entity-framework-6?view=aspnetcore-3.0#reference-full-framework-and-ef6-in-the-asp-net-core-project

CREATE TABLE [dbo].[Blogs]
(
    [BlogId] [INT] IDENTITY(1,1) NOT NULL,
    [Name] [NVARCHAR](200) NULL,
    [Url] [NVARCHAR](200) NULL,

    CONSTRAINT [PK_dbo.Blogs] 
        PRIMARY KEY CLUSTERED ([BlogId] ASC)
                    WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, 
                          IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, 
                          ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO

Answer 1

ASP.NET Core != .NET Core

ASP.NET Core can run on .NET Core or .NET Framework (See Introduction to ASP.NET Core ).

EF Compatibility

EF >= 6.3

From 6.3 EF supports .NET Core.

Announcing Entity Framework 6.3 Preview with .NET Core Support

In fact, the main goal of this release is to facilitate migrating existing applications that use EF 6 to .NET Core 3.0.

EF <6.3

If you want to use EF<6.3 from ASP.Core you need to target .NET framework. The following is from Get Started with ASP.NET Core and Entity Framework 6 .

To use Entity Framework 6, your project has to compile against .NET Framework, as Entity Framework 6 doesn't support .NET Core.

Your solution specifically

The library project in your solution needs to be converted to a .NET Core project.