如何在 Repository 中注入 EntityFramework Core DbContext

Question

大多数在线示例处理 asp.net 并将其 DbContext 注册为启动服务注册表的一部分。

我试过像这样注册我的 DbContext

builder.RegisterType<MyContext>()
    .As<MyContext>()
    .InstancePerLifetimeScope();

builder.RegisterType<DealRepository>()
    .Keyed<IRepository<Deal>>(FiberModule.Key_DoNotSerialize)
    .As<IRepository<Deal>>()
    .SingleInstance();

builder.RegisterType<CardsDialog>()
    .As<IDialog<object>>()
    .InstancePerDependency();

但是我遇到了这个错误

Inheritance security rules violated by type: 'System.Net.Http.WebRequestHandler'. Derived types must either match the security accessibility of the base type or be less accessible.

它甚至更复杂，因为实际的 MessageController.cs 在 Post

上创建了一个新范围

using (var scope = DialogModule.BeginLifetimeScope(Conversation.Container, activity))
{
    var dialog = scope.Resolve<IDialog<object>>();

    await Conversation.SendAsync(activity, () => dialog);

}

如何注册？

编辑：按照建议，使用 InstancePerRequest 解决了问题。但是我还有一个每 X 秒运行一次的 Quartz 作业，它也需要一个存储库。

builder.RegisterType<DealJob>()
    .AsSelf()
    .SingleInstance();

Unable to resolve the type 'BargainBot.Repositories.MyContext' because the lifetime scope it belongs in can't be located. The following services are exposed by this registration: - BargainBot.Repositories.MyContext

Details ---> No scope with a tag matching 'AutofacWebRequest' is visible from the scope in which the instance was requested. If you see this during execution of a web application, it generally indicates that a component registered as per-HTTP request is being requested by a SingleInstance()

此时我应该手动解析一个新的 DbContext 吗？或者也许我应该更改我的回购协议的生命周期？

Edit2：即使删除了整个 Quartz 作业注册，看起来我仍然遇到此错误。

Answer 1

我错了，这不是 IoC 和 DbContext 问题。似乎是在 .NET 平台本身

https://github.com/dotnet/corefx/issues/9846#issuecomment-274707732

添加重定向就成功了

  <dependentAssembly>
    <assemblyIdentity name="System.ComponentModel.TypeConverter" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
    <bindingRedirect oldVersion="0.0.0.0-4.0.1.0" newVersion="4.0.0.0" />
  </dependentAssembly>

Answer 2

正在安装 System.Net.Http 4.3.1 解决了我的问题

Answer 3

我遇到了类似的问题，经过多次来回，以下代码对我有用：

DbContext

 public class SalesDbContext : DbContext
{
    public SalesDbContext(DbContextOptions<SalesDbContext> options) : base(options)
    {
    }

    public DbSet<Domain.Product.Product> Products { get; set; }


    protected override void OnModelCreating(ModelBuilder builder)
    {
        // Configure database attributes
    }



}

存储库

 public class ProductRepository : IProductRepository
{
    private readonly SalesDbContext _db;

    public ProductRepository(SalesDbContext db)
    {
        _db = db;
    }


}

Autofac 模块

 public class DefaultModule : Module
{
    protected override void Load(ContainerBuilder builder)
    {
        // Register Entity Framework
        var dbContextOptionsBuilder = new DbContextOptionsBuilder<SalesDbContext>().UseSqlServer("MyConnectionString");

        builder.RegisterType<SalesDbContext>()
            .WithParameter("options", dbContextOptionsBuilder.Options)
            .InstancePerLifetimeScope(); 

    }
}

如何在 Repository 中注入 EntityFramework Core DbContext

How to inject EntityFramework Core DbContext in Repository

c#

entity-framework

autofac

entity-framework-core

botframework