entity-framework - 代码优先 Entity Framework - 创建 SQL CE DB 时出错

Question

我一直在使用 Entity Framework CTP 和 Code-First，如 this tutorial Scott Guthrie 和 Scott Hanselman 的另一篇文章(无法发布链接，但谷歌搜索“Simple Code First with Entity Framework 4 - Magic Unicorn Feature CTP 4”)。这对于主要的 MVC 应用程序来说工作得很好，但我现在正在尝试添加一个测试项目，它使用一个单独的 SQL CE 数据库。

我已将以下内容添加到 App.Config 文件中:

<connectionStrings>
    <add name="MyData"
        connectionString="Data Source=D:\myProject\myDb.sdf;"
        providerName="System.Data.SqlServerCe.4.0" />
</connectionStrings>

但是，当我尝试运行测试时，它会在尝试创建数据库时抛出以下错误:

Test method MyProjet.Tests.Administration.ModlelTests.Business.TestGetBusinessesList threw exception: System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.TypeInitializationException: The type initializer for 'System.Data.SqlServerCe.SqlCeProviderServices' threw an exception. ---> System.Security.VerificationException: Operation could destabilize the runtime.

使用以下堆栈跟踪:

System.Data.SqlServerCe.SqlCeProviderServices..ctor() System.Data.SqlServerCe.SqlCeProviderServices..cctor() System.RuntimeFieldHandle.GetValue(RtFieldInfo field, Object instance, RuntimeType fieldType, RuntimeType declaringType, Boolean& domainInitialized) System.Reflection.RtFieldInfo.InternalGetValue(Object obj, Boolean doVisibilityCheck, Boolean doCheckConsistency) System.Reflection.RtFieldInfo.InternalGetValue(Object obj, Boolean doVisibilityCheck) System.Reflection.RtFieldInfo.GetValue(Object obj) System.Data.SqlServerCe.ExtensionMethods.SystemDataSqlServerCeSqlCeProviderServices_Instance_GetValue() System.Data.SqlServerCe.ExtensionMethods.SystemDataSqlServerCeSqlCeProviderServices_Instance() System.Data.SqlServerCe.SqlCeProviderFactory.System.IServiceProvider.GetService(Type serviceType) System.Data.Common.DbProviderServices.GetProviderServices(DbProviderFactory factory) System.Data.Common.DbProviderServices.GetProviderServices(DbConnection connection) System.Data.Entity.ModelConfiguration.Internal.Configuration.CodeFirstCachedMetadataWorkspace.GetMetadataWorkspace(DbConnection storeConnection) System.Data.Entity.Infrastructure.DbModel.CreateObjectContext[TContext](DbConnection existingConnection) System.Data.Entity.Internal.LazyInternalContext.InitializeFromModel(DbModel model) System.Data.Entity.Internal.LazyInternalContext.InitializeContext() System.Data.Entity.Internal.InternalContext.Initialize() System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType) System.Data.Entity.Internal.Linq.EfInternalQuery1.Initialize()
System.Data.Entity.Internal.Linq.EfInternalQuery1.Include(String path) System.Data.Entity.Infrastructure.DbQuery`1.Include(String path) MyProjet.Areas.Administration.Models.BusinessModel.GetBusinesses() in D:\projects2010\MyProjet\MyProjet\Areas\Administration\Models\BusinessModel.cs: line 47 MyProjet.Tests.Administration.ModlelTests.Business.TestGetBusinessesList() in D:\projects2010\MyProjet\MyProjet.Tests\Administration\ModlelTests\Business.cs: line 45

我已尝试替换 MVC 应用程序中现有的 MyData 连接字符串，它工作正常。仅当将其添加到测试项目时才会导致此问题。此外，当指向 SQL 或 SQL Express 数据库时，测试项目可以正常工作。

一直在纠结这个问题，就是想不通。我确定我忽略了一些简单的事情。

Answer 1

尝试使用


Database.DefaultConnectionFactory = new SqlCeConnectionFactory("System.Data.SqlServerCe.4.0");


有关示例，请参阅我的博客文章 http://www.arrangeactassert.com/code-first-entity-framework-unit-test-examples/