asp.net 5 (vnext) and entity framework 6

Question

I'm working on adding an Entity Framework data context to an ASP.NET 5 class library and I keep getting errors that System.Data.Entity is not referenced.

Adding a reference to it only works if the build target is set to .net 4.5.1. This doesn't work for .net core 5.

I'm using VS 2015 RC and the DNVM version of ASP.NET 5 installed is 1.0.0-beta4.

Any ideas if this has been moved or why it's not working?

Edit: added the project.json file

{
    "version": "1.0.0-*",
    "description": "",
    "authors": [ "" ],
    "tags": [ "" ],
    "projectUrl": "",
    "licenseUrl": "",

    "dependencies": {
        "EntityFramework": "6.1.3",
        "Microsoft.DataAnnotations": "1.0.0-beta1"
    },

    "frameworks": {
        "dnx451": { }
        "dnxcore50": {
            "dependencies": {
                "System.Collections": "4.0.10-beta-22816",
                "System.Linq": "4.0.0-beta-22816",
                "System.Threading": "4.0.10-beta-22816",
                "Microsoft.CSharp": "4.0.0-beta-22816"
            }
        }
    }
}

Answer 1

EntityFramework 6 is not compatible with ASP.Net core 5, it's why you have this error.
If you want to use EF6, you must untarget dnxcore50.

Edit: add sample to untarget 'dnxcore50
Your project.json will be:

{
    "version": "1.0.0-*",
    "description": "",
    "authors": [ "" ],
    "tags": [ "" ],
    "projectUrl": "",
    "licenseUrl": "",

    "dependencies": {
        "EntityFramework": "6.1.3",
        "Microsoft.DataAnnotations": "1.0.0-beta1"
    },

    "frameworks": {
        "dnx451": { }
        }
    }
}

Or, use EntityFramework 7
Edit: add sample to use EF7
Assuming you want to use SqlServer and commands to generate migrations, your project.json will be:

{
    "version": "1.0.0-*",
    "description": "",
    "authors": [ "" ],
    "tags": [ "" ],
    "projectUrl": "",
    "licenseUrl": "",

    "dependencies": {
        "EntityFramework.Commands": "7.0.0-beta4",
        "EntityFramework.SqlServer": "7.0.0-beta4",
        "Microsoft.DataAnnotations": "1.0.0-beta1"
    },

    "commands": {
         "ef": "EntityFramework.Commands"
    },

    "frameworks": {
        "dnx451": { }
        "dnxcore50": {
            "dependencies": {
                "System.Collections": "4.0.10-beta-22816",
                "System.Linq": "4.0.0-beta-22816",
                "System.Threading": "4.0.10-beta-22816",
                "Microsoft.CSharp": "4.0.0-beta-22816"
            }
        }
    }
}