.NET Core 3.1 and Could not load file or assembly System.Data.Entity, Version=4.0.0.0

Question

What Nuget package is System.Data.Entity in?

I am converting a .NET Framework 4.5 app to .NET Core 3.1. In .NET Framework, it is using System.Linq.Dynamic, and the app is crashing when running this code:

var results = report.GroupBy(filter.ID, "it")
                    .Select($"new (it.Key as MainID, it as MyModel)");

With this error message:

System.IO.FileNotFoundException: Could not load file or assembly 'System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'. The system cannot find the file specified. File name: 'System.Data.Entity, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' at System.Linq.Dynamic.ExpressionParser..cctor()

Note: it does compile correctly

thanks

edit: The System.Linq.Dynamic Nuget package is installed.

You can have a look at this package and this GitHub repo I'm not sure, that they are same, but it should help you — Pavel Anikhouski
@PavelAnikhouski that did, had to add .AsQueryable() but it worked perfectly! if you add this as an answer I will give you credit — Xaphann

Xaphann Xaphann · Accepted Answer · 2020-01-07T18:24:41

One point I would like to add to @PavelAnikhouski, a very minor change needs to be made to the code. You have to add AsQueryable() to the collection.

var results = report.AsQueryable()
                .GroupBy(filter.ID, "it")
                .Select($"new (it.Key as MainID, it as MyModel)");

.NET Core 3.1 and Could not load file or assembly System.Data.Entity, Version=4.0.0.0

2 Answers