Question: EF Core 5 Error

[andrebarsotti]

Hello,

I was runing a simple EF Core study with script files with the code bellow:

#!/usr/bin/env dotnet-script
#r "nuget: Microsoft.EntityFrameworkCore.Sqlite, 5.0.10"
#r "nuget: Microsoft.EntityFrameworkCore.Design, 5.0.10"
using Microsoft.EntityFrameworkCore;

Run();

private static void Run()
{
    using (var db = new BloggingContext())
    {
        db.Database.Migrate();

        // Note: This sample requires the database to be created before running.
        Console.WriteLine($"Database path: {db.DbPath}.");
        
        // Create
        Console.WriteLine("Inserting a new blog");
        db.Add(new Blog { Url = "http://blogs.msdn.com/adonet" });
        db.SaveChanges();

        // Read
        Console.WriteLine("Querying for a blog");
        var blog = db.Blogs
            .OrderBy(b => b.BlogId)
            .First();

        // Update
        Console.WriteLine("Updating the blog and adding a post");
        blog.Url = "https://devblogs.microsoft.com/dotnet";
        blog.Posts.Add(
            new Post { Title = "Hello World", Content = "I wrote an app using EF Core!" });
        db.SaveChanges();

        // Delete
        Console.WriteLine("Delete the blog");
        db.Remove(blog);
        db.SaveChanges();
    }
}

public class BloggingContext : DbContext
{
    public DbSet<Blog> Blogs { get; set; }
    public DbSet<Post> Posts { get; set; }

    public string DbPath { get; private set; }

    public BloggingContext()
    {
        var folder = Environment.SpecialFolder.LocalApplicationData;
        var path = Environment.GetFolderPath(folder);
        DbPath = $"{path}{System.IO.Path.DirectorySeparatorChar}blogging.db";
    }

    // The following configures EF to create a Sqlite database file in the
    // special "local" folder for your platform.
    protected override void OnConfiguring(DbContextOptionsBuilder options)
        => options.UseSqlite($"Data Source={DbPath}");
}

public class Blog
{
    public int BlogId { get; set; }
    public string Url { get; set; }

    public List<Post> Posts { get; } = new List<Post>();
}

public class Post
{
    public int PostId { get; set; }
    public string Title { get; set; }
    public string Content { get; set; }

    public int BlogId { get; set; }
    public Blog Blog { get; set; }
}

When I execute dotnet script main.csx the flowing error appears:

System.IO.FileLoadException: Could not load file or assembly 'Microsoft.Extensions.DependencyInjection, Version=5.0.0.1, Culture=neutral, PublicKeyToken=adb9793829ddae60'. Could not find or load a specific file. (0x80131621)
File name: 'Microsoft.Extensions.DependencyInjection, Version=5.0.0.1, Culture=neutral, PublicKeyToken=adb9793829ddae60'
---> System.IO.FileLoadException: Could not load file or assembly 'Microsoft.Extensions.DependencyInjection, Version=5.0.0.1, Culture=neutral, PublicKeyToken=adb9793829ddae60'.
  at System.Runtime.Loader.AssemblyLoadContext.LoadFromPath(IntPtr ptrNativeAssemblyLoadContext, String ilPath, String niPath, ObjectHandleOnStack retAssembly)
  at System.Runtime.Loader.AssemblyLoadContext.LoadFromAssemblyPath(String assemblyPath)
  at System.Reflection.Assembly.LoadFrom(String assemblyFile)
  at System.Reflection.Assembly.LoadFromResolveHandler(Object sender, ResolveEventArgs args)
  at System.Runtime.Loader.AssemblyLoadContext.InvokeResolveEvent(ResolveEventHandler eventHandler, RuntimeAssembly assembly, String name)
  at System.Runtime.Loader.AssemblyLoadContext.OnAssemblyResolve(RuntimeAssembly assembly, String assemblyFullName)
  at Microsoft.EntityFrameworkCore.Internal.ServiceProviderCache.<>c__DisplayClass4_0.<GetOrAdd>g__BuildServiceProvider|3()
  at Microsoft.EntityFrameworkCore.Internal.ServiceProviderCache.<>c__DisplayClass4_0.<GetOrAdd>b__2(Int64 k)
  at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
  at Microsoft.EntityFrameworkCore.Internal.ServiceProviderCache.GetOrAdd(IDbContextOptions options, Boolean providerRequired)
  at Microsoft.EntityFrameworkCore.DbContext..ctor(DbContextOptions options)
  at Microsoft.EntityFrameworkCore.DbContext..ctor()
  at Submission#0.BloggingContext..ctor() in /workspace/ef-core-sample/main.csx:line 49
  at Submission#0.Run() in /workspace/ef-core-sample/main.csx:line 10
  at Submission#0.<<Initialize>>d__0.MoveNext() in /workspace/ef-core-sample/main.csx:line 6
--- End of stack trace from previous location ---
  at Dotnet.Script.Core.ScriptRunner.Execute[TReturn](String dllPath, IEnumerable`1 commandLineArgs) in C:\Users\VssAdministrator\AppData\Local\Temp\tmpBFB\Dotnet.Script.Core\ScriptRunner.cs:line 110

Probably I'm doing something wrong, could somebody help me?

[seesharper]

This is probably because dotnet script itself references an older version of Microsoft.Extensions.DependencyInjection

Try executing the script with --isolated-load-context

[andrebarsotti]

Thank you @seesharper, it works.