ASP.NET 5 EntityFramework.Core 7.0.0-rc1-final issue - 编译器想要引用7.0.0.0，但未找到

您应该从依赖项中删除 "EntityFramework" （删除"EntityFramework": "7.0.0-beta4" ）并使用

"EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final",
"EntityFramework.MicrosoftSqlServer.Design": "7.0.0-rc1-final",
"EntityFramework.Commands": "7.0.0-rc1-final"

只要。如果由于以下依赖项添加了"EntityFramework.Core": "7.0.0-rc1-final"则无需显式添加"EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final" ：

"EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final":
    "EntityFramework.Relational": "7.0.0-rc1-final":
        "EntityFramework.Core": "7.0.0-rc1-final"

我的意思是EntityFramework.MicrosoftSqlServer需要EntityFramework.Relational ，它需要EntityFramework.Core 。

您还应验证global.json包含"sdk": { "version": "1.0.0-rc1-update1" } 。

更新 ：我检查了你上传的测试项目。它有很多小问题。我修改了它。您可以在此处下载修改后的项目。 不要忘记修复appsettings.json使用的ConnectionString ，它包含我在我用过的Server 。

最重要的变化是使用更简单的BookContext.cs ：

using Microsoft.Data.Entity;

namespace apiservice.Models {
    public class BookContext : DbContext {
        public DbSet<Author> Authors { get; set; }
        public DbSet<Book> Books { get; set; }
    }
}

使用以下SampleData.cs

using System;
using System.Linq;
using Microsoft.Data.Entity;
using Microsoft.Extensions.DependencyInjection;

namespace apiservice.Models
{
    public static class SampleData
    {
        public static void Initialize(IServiceProvider serviceProvider) {
            var context=serviceProvider.GetService<BookContext>();
            context.Database.Migrate();
            if (!context.Books.Any()) {
                var austen = context.Authors.Add(
                    new Author { LastName = "Austen", FirstName = "Jane" }).Entity;
                var dickens = context.Authors.Add(
                    new Author { LastName = "Dickens", FirstName = "Charles" }).Entity;
                var cervantes = context.Authors.Add(
                    new Author { LastName = "Cervantes", FirstName = "Miguel" }).Entity;

                context.Books.AddRange(
                    new Book {
                        Title = "Pride and Prejudice",
                        Year = 1813,
                        Author = austen,
                        Price = 9.99M,
                        Genre = "Comedy of manners"
                    },
                    new Book {
                        Title = "Northanger Abbey",
                        Year = 1817,
                        Author = austen,
                        Price = 12.95M,
                        Genre = "Gothic parody"
                    },
                    new Book {
                        Title = "David Copperfield",
                        Year = 1850,
                        Author = dickens,
                        Price = 15,
                        Genre = "Bildungsroman"
                    },
                    new Book {
                        Title = "Don Quixote",
                        Year = 1617,
                        Author = cervantes,
                        Price = 8.95M,
                        Genre = "Picaresque"
                    }
                );

                context.SaveChanges(); 
            }
        }
    }    
}

project.json与以下dependencies部分的用法：

{
  "dependencies": {
    "Microsoft.AspNet.Diagnostics": "1.0.0-rc1-final",
    "Microsoft.AspNet.IISPlatformHandler": "1.0.0-rc1-final",
    "Microsoft.AspNet.Mvc": "6.0.0-rc1-final",
    "Microsoft.AspNet.Mvc.TagHelpers": "6.0.0-rc1-final",
    "Microsoft.AspNet.Server.Kestrel": "1.0.0-rc1-final",
    "Microsoft.AspNet.StaticFiles": "1.0.0-rc1-final",
    "Microsoft.AspNet.Tooling.Razor": "1.0.0-rc1-final",
    "Microsoft.Extensions.Configuration.FileProviderExtensions": "1.0.0-rc1-final",
    "Microsoft.Extensions.Configuration.Json": "1.0.0-rc1-final",
    "Microsoft.Extensions.Logging": "1.0.0-rc1-final",
    "Microsoft.Extensions.Logging.Console": "1.0.0-rc1-final",
    "Microsoft.Extensions.Logging.Debug": "1.0.0-rc1-final",
    "Microsoft.Extensions.DependencyInjection": "1.0.0-rc1-final",
    "Microsoft.Extensions.CodeGenerators.Mvc": "1.0.0-rc1-final",
    "Microsoft.VisualStudio.Web.BrowserLink.Loader": "14.0.0-rc1-final",
    "EntityFramework.MicrosoftSqlServer": "7.0.0-rc1-final",
    "EntityFramework.MicrosoftSqlServer.Design": "7.0.0-rc1-final",
    "EntityFramework.Commands": "7.0.0-rc1-final",
    "System.Net.Http": "4.0.1-beta-23516",
    "Microsoft.Net.Http": "2.2.29",
    "Newtonsoft.Json": "8.0.1"
  },
  "commands": {
    "web": "Microsoft.AspNet.Server.Kestrel",
    "ef": "EntityFramework.Commands"
  },
  "frameworks": {
    "dnx451": { },
    "dnxcore50": { }
  }
}

修复appsettings.json来自

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Verbose",
      "System": "Information",
      "Microsoft": "Information"
    },
    "Data": {
        "DefaultConnection":{
            "ConnectionString": "Server=localhost;Database=BookStore;User Id=sa; Password=******;Trusted_Connection=true;"
        }
    }
  }
}

至

{
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Verbose",
      "System": "Information",
      "Microsoft": "Information"
    }
  },
  "Data": {
    "DefaultConnection": {
      "ConnectionString": "Server=localhost;Database=BookStore;User Id=sa; Password=******;Trusted_Connection=true;"
    }
  }
}

（ Data 不应该在Logging下 ）

以及以下Startup.cs的用法

using apiservice.Models;
using Microsoft.AspNet.Builder;
using Microsoft.AspNet.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Data.Entity;


namespace apiservice
{
    public class Startup
    {
        public static IConfigurationRoot Configuration {get; set;}

        public Startup(IHostingEnvironment env)
        {
            // Set up configuration sources.
            var builder = new ConfigurationBuilder()
                .AddJsonFile("appsettings.json")
                .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
                .AddEnvironmentVariables();
            Configuration = builder.Build();
        }

        // This method gets called by the runtime. Use this method to add services to the container.
        public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddEntityFramework()
                .AddSqlServer()
                .AddDbContext<BookContext>(options => 
                    options.UseSqlServer(Configuration["Data:DefaultConnection:ConnectionString"])
                );

            services.AddMvc();
        }

        public void Configure(IApplicationBuilder app, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole(Configuration.GetSection("Logging"));
            loggerFactory.AddDebug();

            // we need to execute the following two commands before

            //    dnu restore
            //    dnx ef migrations add Initial
            //    dnx ef database update   

            // For more details on creating database during deployment see http://go.microsoft.com/fwlink/?LinkID=615859
            try
            {
                using (var serviceScope = app.ApplicationServices.GetRequiredService<IServiceScopeFactory>()
                    .CreateScope())
                {
                    serviceScope.ServiceProvider.GetService<BookContext>()
                         .Database.Migrate();
                }
            }
            catch { }

            app.UseIISPlatformHandler();

            app.UseStaticFiles();

            app.UseMvc(routes =>
            {
                routes.MapRoute(
                    name: "default",
                    template: "{controller=Home}/{action=Index}/{id?}");
            });

            SampleData.Initialize(app.ApplicationServices);
        }

        // Entry point for the application.
        public static void Main(string[] args) => WebApplication.Run<Startup>(args);
    }
}

我在Configure方法的注释中写道，应该执行命令

dnx ef migrations add Initial
dnx ef database update

恢复所有包后。 dnx ef migrations add Initial将在项目中使用20160101205609_Initial.cs和BookContextModelSnapshot.cs等文件创建其他Migrations文件夹。 appsettings.json定义的数据库将由dnx ef database update创建，并且在与程序分叉期间将填充来自SampleData.cs测试数据。

顺便说一句，我将package.json移动到包文件夹中（与project.json处于同一级别）。您不使用这些包，但该移动使得npm包在Visual Studio中可见和管理。