Reference .NET Core 1.0 library from WPF

Question

I am currently developing a desktop application in WPF, which uses an .NET Core library to make porting to different platforms easier. However, I cannot seem to reference the .NET Core library from the WPF app.

I tried the follwing solutions:

• Reference the project: Visual Studio complains about the project not being an .exe or .dll even though it is.

• Reference the compiled .dll: This is really ugly, but it seems to work at first. Intellisense is OK with it and the WPF project compiles just fine. But as soon as I want to use any functionality from the .NET Core project a BadImageFormatException is thrown.

• dotnet pack the project and reference the .nupkg: Installs a bunch of additional packages and throws a BadImageFormatException when any functionality is used.

From what I can gather there are two options here:

• Do something really hacky like making a .NET Core Console project and passing all objects as strings between the two programs

Or:

• Just give up on .NET Core and use EF6.

Here's my project.json:

{
  "version": "1.0.0-*",

  "buildOptions": {
    "debugType": "portable",
    "emitEntryPoint": true
  },

  "dependencies": {
    "Microsoft.EntityFrameworkCore.Sqlite": "1.0.0",
    "Microsoft.EntityFrameworkCore.Design": {
      "version": "1.0.0-preview2-final",
      "type": "build"
    }
  },

  "frameworks": {
    "netcoreapp1.0": {
      "dependencies": {
        "Microsoft.NETCore.App": {
          "type": "platform",
          "version": "1.0.0"
        }
      },
      "imports": "dnxcore50"
    },
    "dnx451": {}
  },

  "tools": {
    "Microsoft.EntityFrameworkCore.Tools": "1.0.0-preview2-final"
  }
}

I tried both dnx451 and net451. The WPF project is also targeting .net 4.5.1. I am using "Visual Studio 2015 Update 3" with ".NET Core 1.0.1 VS 2015 Tooling Preview 2".

Answer 1

Your project.json isn't correct for a library. A library project should look like:

{
  "dependencies": {
      "Microsoft.EntityFrameworkCore.Sqlite": "1.0.0",
      "Microsoft.EntityFrameworkCore.Design": {
        "version": "1.0.0-preview2-final",
        "type": "build"
      }
  },
  "frameworks": {
    "net451": { },
    "netstandard1.3": {
      "dependencies": {
        "NETStandard.Library": "1.6.0"
      }
    }
  },
  "tools": {
    "Microsoft.EntityFrameworkCore.Tools": "1.0.0-preview2-final"
  }
}

When you run dotnet pack, two DLLs will be produced: one for .NET 4.5.1 and one for .NET Standard 1.3 (or whichever netstandard you want to target). The .NET 4.5.1 DLL should be compatible with your WPF project.