EF Core - 尚未为此DbContext配置任何数据库提供程序

Question

我是EF Core 1.0的新手.在数据库迁移期间运行以下命令时出现以下错误

命令

 migrations add ApplicationUserIsActive -c ApplicationDbContext

错误:

System.InvalidOperationException:尚未为此DbContext配置数据库提供程序.可以通过覆盖DbContext.OnConfiguring方法或在应用程序服务提供程序上使用AddDbContext来配置提供程序.如果使用AddDbContext,那么还要确保您的DbContext类型在其构造函数中接受DbContextOptions对象,并将其传递给DbContext的基础构造函数.

StartUp.cs

public class Startup
{
    public IConfigurationRoot Configuration { get; set; }

    public Startup(IHostingEnvironment env)
    {
        var builder = new ConfigurationBuilder()
            .SetBasePath(env.ContentRootPath)
            .AddJsonFile("appsettings.json");

        Configuration = builder.Build();
    }

    public void ConfigureServices(IServiceCollection services)
    {

        services.AddEntityFrameworkSqlServer()
            .AddDbContext<ApplicationDbContext>((serviceProvider, options) =>
options.UseSqlServer("Server=(localdb)\\mssqllocaldb;Database=employee;Trusted_Connection=True;MultipleActiveResultSets=true;")
       .UseInternalServiceProvider(serviceProvider));

        services.AddEntityFrameworkSqlServer()
            .AddDbContext<EmplooyeeDbContext>((serviceProvider, options) =>
options.UseSqlServer("Server=(localdb)\\mssqllocaldb;Database=employee;Trusted_Connection=True;MultipleActiveResultSets=true;")
       .UseInternalServiceProvider(serviceProvider));

        services.AddTransient<IUserContext, SeedUserContext>();
    }

}

.csproj文件

 <ItemGroup>
<PackageReference Include="Microsoft.EntityFrameworkCore.Tools" Version="1.0.0">
  <PrivateAssets>All</PrivateAssets>
</PackageReference>
<PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="1.0.3" />
<PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="1.0.2" />
<PackageReference Include="Microsoft.Extensions.Logging" Version="1.0.2" />
<PackageReference Include="Microsoft.Extensions.Logging.Console" Version="1.0.2" />
<PackageReference Include="Microsoft.Extensions.Logging.Debug" Version="1.0.2" />
<PackageReference Include="Microsoft.Extensions.Configuration.FileExtensions" Version="1.0.2" />
<PackageReference Include="Microsoft.Extensions.Configuration.Json" Version="1.0.2" />
<PackageReference Include="Microsoft.AspNetCore.Mvc.DataAnnotations" Version="1.0.3" />
<PackageReference Include="Newtonsoft.Json" Version="9.0.1" />

但是,当我执行其他DBContext的迁移命令,即" EmplooyeeDbContext " 时,迁移命令工作正常.

我该如何解决这个问题？

Answer 1

我想出了这个问题.这是由于" ApplicationDbContext " 的默认构造函数导致了问题.删除" ApplicationDbContext " 的默认构造函数后,一切正常.

感谢您的支持.