我一直在尝试遵循本教程... http://www.asp.net/mvc/tutorials/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application但我不断收到以下错误...

system.invalidoperationexception = {"Failed to set database initializer of type 'WeddingPreparations.Dal.WeddingInitializer, KevinLisaWedding' for DbContext type 'WeddingPreparations.Dal.WeddingContext' specified in the application configuration. See inner exception for details."}

内部异常是...

{"Could not load type 'WeddingPreparations.Dal.WeddingContext' from assembly 'EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'.":"WeddingPreparations.Dal.WeddingContext"}

堆栈跟踪是...

   at System.Data.Entity.Internal.InitializerConfig.TryGetInitializer(Type requiredContextType, String contextTypeName, String initializerTypeName, Boolean isDisabled, Func`1 initializerArgs, Func`3 exceptionMessage)
   at System.Data.Entity.Internal.InitializerConfig.<>c__DisplayClass6.<TryGetInitializerFromEntityFrameworkSection>b__1(ContextElement e)
   at System.Linq.Enumerable.WhereSelectEnumerableIterator`2.MoveNext()
   at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
   at System.Data.Entity.Internal.InitializerConfig.TryGetInitializerFromEntityFrameworkSection(Type contextType)
   at System.Data.Entity.Internal.InitializerConfig.TryGetInitializer(Type contextType)
   at System.Data.Entity.Infrastructure.DependencyResolution.AppConfigDependencyResolver.GetServiceFactory(Type type, String name)
   at System.Data.Entity.Infrastructure.DependencyResolution.AppConfigDependencyResolver.<>c__DisplayClass1.<GetService>b__0(Tuple`2 t)
   at System.Collections.Concurrent.ConcurrentDictionary`2.GetOrAdd(TKey key, Func`2 valueFactory)
   at System.Data.Entity.Infrastructure.DependencyResolution.AppConfigDependencyResolver.GetService(Type type, Object key)
   at System.Data.Entity.Infrastructure.DependencyResolution.ResolverChain.<>c__DisplayClass3.<GetService>b__0(IDbDependencyResolver r)
   at System.Linq.Enumerable.WhereSelectArrayIterator`2.MoveNext()
   at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source, Func`2 predicate)
   at System.Data.Entity.Infrastructure.DependencyResolution.ResolverChain.GetService(Type type, Object key)
   at System.Data.Entity.Infrastructure.DependencyResolution.CompositeResolver`2.GetService(Type type, Object key)
   at System.Data.Entity.Infrastructure.DependencyResolution.DbDependencyResolverExtensions.GetService(IDbDependencyResolver resolver, Type type)
   at System.Data.Entity.Internal.InternalContext.PerformDatabaseInitialization()
   at System.Data.Entity.Internal.LazyInternalContext.<InitializeDatabase>b__4(InternalContext c)
   at System.Data.Entity.Internal.RetryAction`1.PerformAction(TInput input)
   at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabaseAction(Action`1 action)
   at System.Data.Entity.Internal.LazyInternalContext.InitializeDatabase()
   at System.Data.Entity.Internal.InternalContext.Initialize()
   at System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType)
   at System.Data.Entity.Internal.Linq.InternalSet`1.Initialize()
   at System.Data.Entity.Internal.Linq.InternalSet`1.GetEnumerator()
   at System.Data.Entity.Infrastructure.DbQuery`1.System.Collections.Generic.IEnumerable<TResult>.GetEnumerator()
   at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)
   at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)
   at KevinLisaWedding.Controllers.HomeController.Index() in c:\Users\kdonde\Documents\Visual Studio 2013\Projects\KevinLisaWedding\KevinLisaWedding\Controllers\HomeController.cs:line 14
   at lambda_method(Closure , ControllerBase , Object[] )
   at System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
   at System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
   at System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.ActionInvocation.InvokeSynchronousActionMethod()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.<BeginInvokeSynchronousActionMethod>b__36(IAsyncResult asyncResult, ActionInvocation innerInvokeState)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResult`2.CallEndDelegate(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncResultWrapper.WrappedAsyncResultBase`1.End()
   at System.Web.Mvc.Async.AsyncResultWrapper.End[TResult](IAsyncResult asyncResult, Object tag)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.EndInvokeActionMethod(IAsyncResult asyncResult)
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3c()
   at System.Web.Mvc.Async.AsyncControllerActionInvoker.AsyncInvocationWithFilters.<>c__DisplayClass45.<InvokeActionMethodFilterAsynchronouslyRecursive>b__3e()

我也到处搜索为什么我会遇到这个错误而没有任何运气，我已经下载了完成的项目并将它与我的进行比较但没有任何运气。

我目前的代码如下。

在 WeddingPreparations 项目中......

namespace WeddingPreparations.Dal
{
    public class WeddingContext : DbContext
    {
        public WeddingContext()
            : base("WeddingContext")  
        {

        }

        // Any entities reference by this class will be implicitly included.
        public DbSet<Invitee> Invitees { get; set; }

        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {
            modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
            //base.OnModelCreating(modelBuilder);
        }
    }
}

和

namespace WeddingPreparations.Dal
{
    public class WeddingInitializer : System.Data.Entity.DropCreateDatabaseIfModelChanges<WeddingContext>
    {
        protected override void Seed(WeddingContext context)
        {
            //base.Seed(context);
            var invitees = new List<Invitee>
            {
                new Invitee{ FirstName= "FName1", LastName= "LName1", Attending = true, HotelRoomRequired= true, Notes="I'm the groom! :)"},
                new Invitee{ FirstName= "FName2", LastName= "LName2", Attending = true, HotelRoomRequired= true, Notes="I'm the bride! :)"}

            };
            invitees.ForEach(i => context.Invitees.Add(i));
            context.SaveChanges();
        }
    }
}

我在这个项目中的模型如下

namespace WeddingPreparations.Models
{
    public class Invitee
    {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public bool Attending { get; set; }
        public bool HotelRoomRequired { get; set; }
        public string Notes { get; set; }
     }
}

在 mvc 项目中，我有以下 web.config 文件......

<?xml version="1.0" encoding="utf-8"?>
<!--
  For more information on how to configure your ASP.NET application, please visit
  http://go.microsoft.com/fwlink/?LinkId=301880
  -->
<configuration>
  <configSections>

    <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
  <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 --></configSections>
  <connectionStrings>
    <add name="WeddingContext" connectionString="Data Source=(LocalDb)\v11.0;Initial Catalog=WeddingInvites;Integrated Security=SSPI;" providerName="System.Data.SqlClient" />
  </connectionStrings>
  <appSettings>
    <add key="webpages:Version" value="3.0.0.0" />
    <add key="webpages:Enabled" value="false" />
    <add key="ClientValidationEnabled" value="true" />
    <add key="UnobtrusiveJavaScriptEnabled" value="true" />
  </appSettings>
  <system.web>
    <compilation debug="true" targetFramework="4.5" />
    <httpRuntime targetFramework="4.5" />
  </system.web>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-5.0.0.0" newVersion="5.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Optimization" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="1.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-1.5.2.14234" newVersion="1.5.2.14234" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="Ninject" publicKeyToken="c7192dc5380945e7" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-3.2.0.0" newVersion="3.2.0.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
  <system.webServer>
    <handlers>
      <remove name="ExtensionlessUrlHandler-Integrated-4.0" />
      <remove name="OPTIONSVerbHandler" />
      <remove name="TRACEVerbHandler" />
      <add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="*" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
    </handlers>
  </system.webServer>
  <entityFramework>
    <contexts>
      <context type="WeddingPreparations.Dal.WeddingContext">
        <databaseInitializer type="WeddingPreparations.Dal.WeddingInitializer, KevinLisaWedding" />
      </context>
    </contexts>
    <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework" >
    <parameters>
      <parameter value="v11.0"/>
    </parameters>
    </defaultConnectionFactory>
    <providers>
      <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
    </providers>
  </entityFramework>
</configuration>

在我的家庭 Controller 中，我正在执行以下代码......

WeddingPreparations.Dal.WeddingContext ctx = new WeddingPreparations.Dal.WeddingContext();
var x = ctx.Invitees.ToList();

如果我没记错的话应该创建数据库并用初始化程序中指定的数据为它播种......但是我得到的只是那个错误而且我似乎无法弄清楚......任何表示赞赏。

更新

我尝试像他们在教程中那样重新创建项目，但我仍然遇到同样的错误。肯定是少了一些代码……要么是我遗漏了……要么就是教程中没有。

最佳答案

在你的 web.config 文件中你有这个:

<contexts>
    <context type="WeddingPreparations.Dal.WeddingContext">
        <databaseInitializer type="WeddingPreparations.Dal.WeddingInitializer, KevinLisaWedding" />
    </context>
</contexts>

这表示在名为 KevinLisaWedding 的程序集中查找名为 WeddingPreparations.Dal.WeddingInitializer 的类。由于您的程序集名为 WeddingPreparations，您需要将配置更改为:

<contexts>
    <context type="WeddingPreparations.Dal.WeddingContext, WeddingPreparations">
        <databaseInitializer type="WeddingPreparations.Dal.WeddingInitializer, WeddingPreparations" />
    </context>
</contexts>

关于c# - 使用 EF6 加载数据库初始值设定项时出错，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24542605/