Entity Framework DbContext 是用错误的构造函数初始化的

Question

在我的 ASP.NET Core Web API 中，我将 DbContext 添加到服务中：

 services.AddDbContext<OpContext>(options =>  options.UseSqlServer(Configuration["DatabaseConnectionString"]));

问题是我的 dbcontext 作为三个构造函数：

 public partial class UppContext : DbContext
 {
    public UppContext() : base()
    { }

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

    public UppContext(IIdentificationService idService) : base()
    {
        _idService = idService;
    }

而OpContext继承自上面的：

public partial class OpContext : UppContext
{
    public OpContext() : base() { }
    public OpContext(IIdentificationService idService) : base(idService) { }

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

并且它总是调用无参数构造函数，而不是调用带选项的构造函数。因此我的连接不起作用。

这是我在控制器中注入它的地方：

  public RequestController(OpContext dbContext)
    {
        cxt = dbContext;
        persistenceManager = new OpPersistenceManager(dbContext);
    }

这是实际的例外情况：

System.InvalidOperationException HResult=0x80131509 Message=No database provider has been configured for this DbContext. A provider can be configured by overriding the DbContext.OnConfiguring method or by using AddDbContext on the application service provider. If AddDbContext is used, then also ensure that your DbContext type accepts a DbContextOptions object in its constructor and passes it to the base constructor for DbContext.
Source=Microsoft.EntityFrameworkCore StackTrace: at Microsoft.EntityFrameworkCore.Internal.DbContextServices.Initialize(IServiceProvider scopedProvider, IDbContextOptions contextOptions, DbContext context)
at Microsoft.EntityFrameworkCore.DbContext.get_InternalServiceProvider() at Microsoft.EntityFrameworkCore.DbContext.get_ChangeTracker() at Breeze.Persistence.EFCore.EFPersistenceManager`1..ctor(T context)
at Op.Authors.Api.Breeze.OpPersistenceManager..ctor(OpContext dbContext) in C:\dev\UPP\Source\Op\Op.Authors.Api\Breeze\OpPersistenceManager.cs:line 8 at Op.Authors.Api.Controllers.RequestController..ctor(OpContext dbContext) in C:\dev\UPP\Source\Op\Op.Authors.Api\Controllers\RequestController.cs:line 21 at Microsoft.AspNetCore.Mvc.Controllers.ControllerActivatorProvider.<>c__DisplayClass4_0.b__0(ControllerContext controllerContext) at Microsoft.AspNetCore.Mvc.Controllers.ControllerFactoryProvider.<>c__DisplayClass5_0.g__CreateController|0(ControllerContext controllerContext) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted) at Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker.InvokeInnerFilterAsync()

我是不是漏掉了什么？

Answer 1

免责声明：我复制了您的代码，但具有一级继承。

改变

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

至

public OpContext(DbContextOptions<OpContext> options) : base(options)   { }

为我解决了这个问题。

注意 DbContextOptions 的类型参数。

Entity Framework DbContext 是用错误的构造函数初始化的

Entity Framework DbContext is initialized with wrong constructor

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asp.net-core