topic Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0) in .NET Forum

Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

mdoyon1 — Sun, 22 Dec 2024 02:57:58 GMT

I have been spending the past couple of days to connect a database to AutoCAD in order to store attribute data. I used EF6 for AutoCAD 2023 (.Net Framework 4.8) but it gets more complicated with the migration to .Net Core.

The error happens when creating a ApplicationDbContext and some file dll cannot be loaded.

Error message when trying to create a database context:
System.IO.FileLoadException: 'Could not load file or assembly 'Microsoft.Extensions.DependencyInjection.Abstractions, Version=9.0.0.0,

There are only two files in the project for now:
Class1.cs:

using System.Text; using Autodesk.AutoCAD.ApplicationServices; using Autodesk.AutoCAD.DatabaseServices; using Autodesk.AutoCAD.EditorInput; using Autodesk.AutoCAD.Geometry; using Autodesk.AutoCAD.Runtime; using Autodesk.AutoCAD.Windows; using Microsoft.EntityFrameworkCore; using Microsoft.Extensions.DependencyInjection; using Application = Autodesk.AutoCAD.ApplicationServices.Application; [assembly: ExtensionApplication(typeof(DatabaseAutoCAD.ExtensionApplication))] [assembly: CommandClass(typeof(DatabaseAutoCAD.Class1))] namespace DatabaseAutoCAD { public class ExtensionApplication : IExtensionApplication { public void Initialize() { } public void Terminate() { } } public class Class1 { [CommandMethod("CreateProduct")] public void CreateProduct() { using (var db = new ApplicationDbContext()) { db.Database.EnsureCreated(); var product = new Product { Name = "Product 1", Description = "Description 1" }; db.Products.Add(product); db.SaveChanges(); } } } }

entities.cs

using System; using System.Collections.Generic; using System.ComponentModel.DataAnnotations.Schema; using System.ComponentModel.DataAnnotations; using System.Linq; using System.Text; using System.Threading.Tasks; using Microsoft.EntityFrameworkCore; namespace DatabaseAutoCAD { public class Product { [Key] // Primary Key public int Id { get; set; } public string Name { get; set; } = string.Empty; public string? Description { get; set; } // Optional property } public class ApplicationDbContext : DbContext { public DbSet<Product> Products { get; set; } = null!; public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options) : base(options) { } public ApplicationDbContext() : base() { } protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder) { optionsBuilder.UseSqlite("Data Source=app.db"); // Replace with your connection string } protected override void OnModelCreating(ModelBuilder modelBuilder) { base.OnModelCreating(modelBuilder); // Fluent API configurations (optional) modelBuilder.Entity<Product>() .HasIndex(p => p.Name) .IsUnique(); // Ensure the product name is unique } } }

I added the following statement in the project settings in order to copy the file assemblies to the output directory:

The dll is now present in the folder when the build is completed.

Any help would be very much appreciated! Thanks

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

norman.yuan — Sun, 22 Dec 2024 20:22:35 GMT

Since Acad2025 uses .NET 8, you need also upgrade the Entity Framework from 6.x to Miscrosoft.EntityFrameworkCore. It looks to me that you are still using Microsoft.EntityFramework, not Microsoft.EntityFrameworkCore, hence the error. When you install Microsoft.EntityFrameworkCore, Microsoft.Extensions.DepedencyInkection.Abstractions in included in the Nuget package.

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

mdoyon1 — Fri, 27 Dec 2024 17:24:27 GMT

Thank you!

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

brand — Tue, 25 Feb 2025 15:56:48 GMT

I'm running into this problem as well. I am referencing EntityFrameworkCore.

I've also included the CopyLocalLockFileAssemblies element in my .csproj file, and Microsoft.Extensions.DependencyInjection.Abstractions.dll appears in the bin folder when I build the project.

I even went so far as copying Microsoft.Extensions.DependencyInjection.Abstractions.dll into C:\Program Files\Autodesk\Autocad 2025 so that it would be adjacent to acad.exe (this worked previously to solve an issue with another library). But not in this case, I still get the error.

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

ecervantesUSZDX — Tue, 08 Apr 2025 16:07:42 GMT

Did you find any solution? I'm still getting the same error

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

brand — Tue, 08 Apr 2025 16:47:14 GMT

Nope, still stuck and frustrated. Have tried EF Core versions 9.0.0 to 9.0.3, none have worked.

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

kerry_w_brown — Tue, 08 Apr 2025 22:04:54 GMT

@brand

Have you tried one of the version 8 builds of EntityFrameworkCore ?

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

brand — Wed, 09 Apr 2025 15:32:06 GMT

I noticed there's a newly released 9.0.4 version out, which I tried this morning. Same problem.

Yes, I have tried the v8 builds. These have dependencies on components that aren't built on .NET 8. With EF 8.0.15, I don't get the Microsoft.Extensions.DependencyInjection.Abstractions error, but I get this instead.

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

brand — Wed, 09 Apr 2025 20:50:31 GMT

So I decided to try Dapper just to get a **bleeping** connection to the database working from inside Autocad 2025. Via NuGet I added Dapper 2.1.66 and Microsoft.Data.SqlClient 6.0.1. Revised my test query to use a SqlConnection and Dapper extension methods, not too difficult. Loaded up in Autocad and...

Uggh! Did some digging and found a suggestion that you need to add <RuntimeIdentifier>win-x64</RuntimeIdentifier> element to the .csproj file. Did that, which now builds in the Debug\net8.0-windows\win-x64 folder (watch for that during NETLOAD). Ran again and finally got past the Microsoft.Data.SqlClient problem! Then ran into this:

The database I'm connecting to isn't one I use often and I was trying to use a trusted connection. I had to add TrustServerCertificate=True to my connection string.

And finally I'm pulling data from a database!

References:

https://github.com/dotnet/SqlClient/issues/2030
Look for IzharAzati's comment 3/4 of the way through this thread...who was trying to get his Autocad plugin to work :/.
Welcome To Learn Dapper ORM - A Dapper Tutorial for C# and .NET Core

Re: Connect AutoCAD to database using Entity Framework Core (.Net 8.0)

brand — Thu, 22 Jan 2026 20:39:26 GMT

Hmm, not sure why I didn't update this earlier. I finally was able to get EntityFramework working back in August 2025, using 8.0.19 (and I just tested with 8.0.23, still good). My test plugin worked in both Autocad 2025/26. I added the following Nuget packages:

The 9.0.x and 10.0.x versions of EntityFramework do not work with Autocad 2025/26.