Question

.Net Core 1.0.0 - SDK Preview 2（x64）

.Net Core 1.0.0 - VS＆＃34; 15＆＃34;预览2（x64）

.Net Core 1.0.0 - 运行时（x64）

因此，我们将RC1应用更新为上述最新版本。经过几个小时的切换参考后，它就会运行。但是，登录时（AccountController / Login），我收到错误：

public class AccountController : BaseController
{
    public UserManager<ApplicationUser> UserManager { get; private set; }
    public SignInManager<ApplicationUser> SignInManager { get; private set; }
    private readonly IEmailSender EmailSender;

    public AccountController(UserManager<ApplicationUser> userManager, SignInManager<ApplicationUser> signInManager, IEmailSender emailSender)
    {
        UserManager = userManager;
        SignInManager = signInManager;
        EmailSender = emailSender;
    }

    // GET: /Account/Login
    [HttpGet]
    [AllowAnonymous]
    public IActionResult Login(string returnUrl = null)
    {
        ViewBag.ReturnUrl = returnUrl;
        return View();
    }

    //
    // POST: /Account/Login
    [HttpPost]
    [AllowAnonymous]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Login(ViewModels.Account.LoginViewModel model, string returnUrl = null)
    {
        if (ModelState.IsValid)
        {
            // Errs this next line
            var result = await SignInManager.PasswordSignInAsync(model.Email, model.Password, model.RememberMe, false); // <-- ERRS HERE '.PasswordSignInAsync'
            if (result.Succeeded)
                return RedirectToLocal(returnUrl);

            ModelState.AddModelError("", "Invalid email or password.");
            return View(model);
        }

        // If we got this far, something failed, redisplay form
        return View(model);
    }

它会出现以下错误消息：

InvalidOperationException：没有为此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。

这是Startup.cs：

public void ConfigureServices(IServiceCollection services)
    {
        services.Configure<AppSettings>(Configuration.GetSection("AppSettings"));

        // Add EF services to the services container.
        services.AddEntityFrameworkSqlServer()
           .AddDbContext<LogManagerContext>(options =>
              options.UseSqlServer(Configuration["Data:DefaultConnection:Connectionstring"]));

        services.AddSingleton(c => Configuration);

        // Add Identity services to the services container.
        services.AddIdentity<ApplicationUser, IdentityRole>()
            .AddEntityFrameworkStores<LogManagerContext>()
            .AddDefaultTokenProviders();


        // Add MVC services to the services container.
        services.AddMvc();

        services.AddTransient<IHttpContextAccessor, HttpContextAccessor>();

        //Add all SignalR related services to IoC. - Signal R not ready yet - Chad
        //services.AddSignalR();

        //Add InMemoryCache
        services.AddMemoryCache();

        services.AddSession(options =>
        {
            options.IdleTimeout = System.TimeSpan.FromHours(1);
            options.CookieName = ".LogManager";
        });

        // Uncomment the following line to add Web API servcies which makes it easier to port Web API 2 controllers.
        // You need to add Microsoft.AspNet.Mvc.WebApiCompatShim package to project.json
        // services.AddWebApiConventions();
        // Register application services.
        services.AddTransient<IEmailSender, AuthMessageSender>();

    }

    // Configure is called after ConfigureServices is called.
    public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
    {
        app.UseSession();

        // Configure the HTTP request pipeline.
        // Add the console logger.
        //loggerFactory.MinimumLevel = LogLevel.Information; - moved to appsettings.json -chad
        loggerFactory.AddConsole();
        loggerFactory.AddDebug();

        loggerFactory.AddNLog();

        // Add the following to the request pipeline only in development environment.
        if (env.IsDevelopment())
        {
            app.UseBrowserLink();
            app.UseDeveloperExceptionPage();
            //app.UseDatabaseErrorPage(DatabaseErrorPageOptions.ShowAll);
        }
        else
        {
            // Add Error handling middleware which catches all application specific errors and
            // sends the request to the following path or controller action.
            app.UseExceptionHandler("/Home/Error");
        }

        env.ConfigureNLog("NLog.config");

        // Add static files to the request pipeline.
        app.UseStaticFiles();

        // Add cookie-based authentication to the request pipeline.
        app.UseIdentity();

        //SignalR
        //app.UseSignalR();

        // Add MVC to the request pipeline.
        app.UseMvc(routes =>
        {
            routes.MapRoute(
             name: "default",
             template: "{controller}/{action}/{id?}",
             defaults: new { controller = "Home", action = "Index" }
             );

            // Uncomment the following line to add a route for porting Web API 2 controllers.
            // routes.MapWebApiRoute("DefaultApi", "api/{controller}/{id?}");
        });
    }

以上是上下文：

public class ApplicationUser : IdentityUser
{
    // Add Custom Profile Fields
    public string Name { get; set; }
}

public class LogManagerContext : IdentityDbContext<ApplicationUser>
{
    public DbSet<LogEvent> LogEvents { get; set; }
    public DbSet<Client> Clients { get; set; }
    public DbSet<LogEventsHistory> LogEventsHistory { get; set; }
    public DbSet<LogEventsLineHistory> LogEventsLineHistory { get; set; }
    public DbSet<LogRallyHistory> LogRallyHistory { get; set; }
    public DbSet<Flag> Flags { get; set; }
    protected override void OnModelCreating(ModelBuilder builder)
    {

        builder.Entity<LogEvent>().HasKey(x => x.LogId);
        builder.Entity<LogEvent>().ToTable("LogEvents");
        builder.Entity<Client>().HasKey(x => x.ClientId);
        builder.Entity<Client>().ToTable("Clients");
        builder.Entity<LogEventsHistory>().HasKey(x => x.HistoryId);
        builder.Entity<Flag>().HasKey(x => x.FlagId);
        builder.Entity<Flag>().ToTable("Flags");
        builder.Entity<LogRallyHistory>().HasKey(x => x.HistoryId);
        builder.Entity<LogEventsLineHistory>().HasKey(x => x.LineHistoryId);

        base.OnModelCreating(builder);
    }

Answer 1

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。

错误消息显示您的DbContext（LogManagerContext）需要一个接受DbContextOptions的构造函数。但我无法在DbContext中找到这样的构造函数。因此，添加下面的构造函数可能会解决您的问题。

    public LogManagerContext(DbContextOptions options) : base(options)
    {
    }

修改评论

如果您未明确注册IHttpContextAccessor，请使用以下代码：

services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();

Answer 2

我可以通过在DConContextOptionsBuilder中添加连接字符串来覆盖MyContext中的Configuration来解决它：

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
    {
        if (!optionsBuilder.IsConfigured)
        {
            IConfigurationRoot configuration = new ConfigurationBuilder()
               .SetBasePath(Directory.GetCurrentDirectory())
               .AddJsonFile("appsettings.json")
               .Build();
            var connectionString = configuration.GetConnectionString("DbCoreConnectionString");
            optionsBuilder.UseSqlServer(connectionString);
        }
    }

Answer 3

我知道这是旧的，但这个答案仍然适用于较新的核心版本。

如果您的 DbContext 实现与您的启动项目在不同的项目中，并且您运行 ef migrations，您将看到此错误，因为该命令将无法调用应用程序的启动代码让您的数据库提供程序没有配置。要修复它，您必须让 ef migrations 知道他们在哪里。

dotnet ef migrations add MyMigration [-p <relative path to DbContext project>, -s <relative path to startup project>]

-s 和 -p 都是 default to the current folder 的可选项。

Answer 4

这是我找到的解决方案。

https://github.com/aspnet/EntityFramework.Docs/blob/master/entity-framework/core/miscellaneous/configuring-dbcontext.md

通过AddDbContext配置DBContext

public void ConfigureServices(IServiceCollection services)
{
    services.AddDbContext<BloggingContext>(options => options.UseSqlite("Data Source=blog.db"));
}

向您的DBContext类添加新的构造函数

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

    public DbSet<Blog> Blogs { get; set; }
}

向控制器注入上下文

public class MyController
{
    private readonly BloggingContext _context;

    public MyController(BloggingContext context)
    {
      _context = context;
    }

    ...
}

Answer 5

除了接受的答案之外，如果有人在正确执行以下操作后仍然收到错误：

在Startup.cs中：services.AddDbContext<ApplicationDbContext>(options => ... )
在ApplicationDbContext.cs中：public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options) : base(options){}

检查DbContext 类没有任何无参数的公共构造函数（如果有的话需要删除它）。仅供参考，由于某种原因，您可能会添加无参数的公共构造函数，即 Scaffolding DbContext。

详情：ASP.Net Core troubleshooting

Answer 6

重写DbContext的构造方法试试这个：-

public DataContext(DbContextOptions<DataContext> option):base(option) {}

＆＃39;没有为此DbContext配置数据库提供程序＆＃39;在SignInManager.PasswordSignInAsync上

6 个答案: