.net - 'ApplicationDbContext' 不继承自 DbContext

问题描述

我收到此错误：

该类型ApplicationDbContext不继承自DbContext. 该DbMigrationsConfiguration.ContextType属性必须设置为继承自的类型DbContext。

这是我的代码：

using Microsoft.EntityFrameworkCore;
using System;
using System.Collections.Generic;
//using System.Data.Entity;
using System.Linq;
using System.Threading.Tasks;

namespace Manufactura.Models
{
    public class ApplicationDbContext : DbContext
    {
        public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
            : base(options)
        {

        }

        public DbSet<Categories> Categories { get; set; }
        public DbSet<CustomerCities> CustomerCities { get; set; }
        public DbSet<CustomerCountries> CustomerCountries { get; set; }
        public DbSet<CustomerRegions> CustomerRegions { get; set; }
        public DbSet<Customers> Customers { get; set; }
        public DbSet<Employees> Employees { get; set; }
        public DbSet<Payments> Payments { get; set; }
        public DbSet<ProductDetails> ProductDetails { get; set; }
        public DbSet<ProductionOrders> ProductionOrders { get; set; }
        public DbSet<Products> Products { get; set; }
        public DbSet<RawMaterials> RawMaterials { get; set; }
        public DbSet<SaleInvoices> SaleInvoices { get; set; }
        public DbSet<Shippings> Shippings { get; set; }
        public DbSet<SuplierCities> SuplierCities { get; set; }
        public DbSet<SuplierCountries> SuplierCountries { get; set; }
        public DbSet<SuplierInvoices> SuplierInvoices { get; set; }
        public DbSet<SuplierRegions> SuplierRegions { get; set; }
        public DbSet<Supliers> Supliers { get; set; }
        

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            // optionsBuilder.UseSqlServer(@"Server=.\SQLEXPRESS;Database=SchoolDB;Trusted_Connection=True;");

        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            modelBuilder.Entity<Categories>().HasKey(m => m.CategoryId);
            modelBuilder.Entity<CustomerCities>().HasKey(m => m.CustomerCity);
            modelBuilder.Entity<CustomerCountries>().HasKey(m => m.CustomerCountry);
            modelBuilder.Entity<CustomerRegions>().HasKey(m => m.CustomerRegion);
            modelBuilder.Entity<Customers>().HasKey(m => m.CustomerId);
            modelBuilder.Entity<Employees>().HasKey(m => m.EmployeeId);
            modelBuilder.Entity<Payments>().HasKey(m => m.PaymentId);
            modelBuilder.Entity<ProductDetails>().HasKey(m => m.ProductDetailsId);
            modelBuilder.Entity<ProductionOrders>().HasKey(m => m.ProductionOrdersId);
            modelBuilder.Entity<Products>().HasKey(m => m.ProductId);
            modelBuilder.Entity<RawMaterials>().HasKey(m => m.RawMaterialsId);
            modelBuilder.Entity<SaleInvoices>().HasKey(m => m.SaleInvoiceId);
            modelBuilder.Entity<Shippings>().HasKey(m => m.ShippingId);
            modelBuilder.Entity<SuplierCities>().HasKey(m => m.SuplierCity);
            modelBuilder.Entity<SuplierCountries>().HasKey(m => m.SuplierCountry);
            modelBuilder.Entity<SuplierInvoices>().HasKey(m => m.SuplierInvoiceId);
            modelBuilder.Entity<SuplierRegions>().HasKey(m => m.SuplierRegion);
            modelBuilder.Entity<Supliers>().HasKey(m => m.SuplierId);

            modelBuilder.Entity<Products>()
            .HasOne(p => p.Category)
            .WithMany(b => b.Products);

            modelBuilder.Entity<CustomerRegions>()
           .HasOne(p => p.CustomerCountry)
           .WithMany(b => b.CustomerRegions);

            modelBuilder.Entity<CustomerCities>()
           .HasOne(p => p.CustomerRegion)
           .WithMany(b => b.CustomerCities);

            modelBuilder.Entity<Customers>()
           .HasOne(p => p.CustomerCity)
           .WithMany(b => b.Customers);

            modelBuilder.Entity<SaleInvoices>()
           .HasOne(p => p.Customer)
           .WithMany(b => b.SaleInvoices);

            modelBuilder.Entity<Payments>()
           .HasOne(p => p.SaleInvoice)
           .WithMany(b => b.Payments);

            modelBuilder.Entity<ProductDetails>()
           .HasOne(p => p.SaleInvoice)
           .WithMany(b => b.ProductDetails);

            modelBuilder.Entity<Products>()
           .HasOne(p => p.ProductDetail)
           .WithMany(b => b.Products);

            modelBuilder.Entity<Products>()
           .HasOne(p => p.ProductionOrder)
           .WithMany(b => b.Products);

            modelBuilder.Entity<Products>()
           .HasOne(p => p.Employee)
           .WithMany(b => b.Products);

            modelBuilder.Entity<Products>()
           .HasOne(p => p.Category)
           .WithMany(b => b.Products);

            modelBuilder.Entity<ProductionOrders>()
           .HasOne(p => p.RawMaterial)
           .WithMany(b => b.ProductionOrders);

            modelBuilder.Entity<SuplierInvoices>()
           .HasOne(p => p.RawMaterial)
           .WithMany(b => b.SuplierInvoices);

            modelBuilder.Entity<SuplierInvoices>()
           .HasOne(p => p.Suplier)
           .WithMany(b => b.SuplierInvoices);

            modelBuilder.Entity<Supliers>()
           .HasOne(p => p.SuplierCity)
           .WithMany(b => b.Supliers);

            modelBuilder.Entity<SuplierCities>()
           .HasOne(p => p.SuplierRegion)
           .WithMany(b => b.SuplierCities);

            modelBuilder.Entity<SuplierRegions>()
           .HasOne(p => p.SuplierCountry)
           .WithMany(b => b.SuplierRegions);

            base.OnModelCreating(modelBuilder);
        }

    }
}

我已经尝试了该网站所说的所有内容，包括重新启动 VS：

enable-migrations -ProjectName Manufactura -Verbose

Enable-Migrations -ProjectName Manufactura -ContextTypeName Manufactura.Models.ApplicationDbContext

Enable-Migrations -ProjectName Manufactura -ContextTypeName Manufactura.Models.ApplicationDbContext -force

Install-Package EntityFramework -IncludePrerelease

UnInstall-Package EntityFramework 

Install-Package EntityFramework

这是.Net Core 3.1在VS 2019中的应用

如果我取消注释System.Data.Entity，我会收到错误：DbContext是一个模棱两可的参考

没有任何效果。

这是我的应用设置

{
  "ConnectionStrings": {
    "ConnectionString": "Data Source=.;Initial catalog=confecciones;Integrated Security=true"
  },

  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  },
  "AllowedHosts": "*"
}

在 DbContext 上使用 f12，它带我到这里：

namespace Microsoft.EntityFrameworkCore
ublic class DbContext : IDisposable, IAsyncDisposable, IInfrastructure<IServiceProvider>, IDbContextDependencies, IDbSetCache, IDbContextPoolable, IResettableService
    {
        //
        // Resumen:
        //     Initializes a new instance of the Microsoft.EntityFrameworkCore.DbContext class
        //     using the specified options. The Microsoft.EntityFrameworkCore.DbContext.OnConfiguring(Microsoft.EntityFrameworkCore.DbContextOptionsBuilder)
        //     method will still be called to allow further configuration of the options.
        //
        // Parámetros:
        //   options:
        //     The options for this context.
        public DbContext([NotNullAttribute] DbContextOptions options);
        //
        // Resumen:
        //     Initializes a new instance of the Microsoft.EntityFrameworkCore.DbContext class.
        //     The Microsoft.EntityFrameworkCore.DbContext.OnConfiguring(Microsoft.EntityFrameworkCore.DbContextOptionsBuilder)
        //     method will be called to configure the database (and other options) to be used
        //     for this context.
        protected DbContext();

启动代码：

using System;
using System.Collections.Generic;
using System.Linq;
//using System.Data.Entity;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.HttpsPolicy;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using Microsoft.EntityFrameworkCore;
using Manufactura.Models;
using Microsoft.Extensions.Hosting;

namespace Manufactura
{
    public class Startup
    {
        public Startup(IConfiguration configuration)
        {
            Configuration = configuration;
        }

        public IConfiguration Configuration { get; }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            //services.AddRazorPages();
                        
            services.AddDbContext<ApplicationDbContext>(options => options.UseSqlServer(Configuration.GetConnectionString("ConnectionString")));
            services.AddControllers();

        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
        {
            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }
            else
            {
                app.UseExceptionHandler("/Error");
                // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
                app.UseHsts();
            }

            app.UseHttpsRedirection();
            app.UseStaticFiles();

            app.UseRouting();

            app.UseAuthorization();

            app.UseEndpoints(endpoints =>
            {
                endpoints.MapRazorPages();
            });
        }
    }
}

应用设置：

{


  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft": "Warning",
      "Microsoft.Hosting.Lifetime": "Information"
    }
  },
  "AllowedHosts": "*",
  "ConnectionStrings": {
    "ConnectionString": "Data Source=DESKTOP-APHO8VE\\SQLEXPRESS;Initial catalog=confecciones;Integrated Security=true"
  }
}

标签： .netasp.net-core.net-coreentity-framework-core.net-core-3.1

.net - 'ApplicationDbContext' 不继承自 DbContext

问题描述

解决方案

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