c# - 运行代码首先迁移更新数据库时出错

Question

我在迁移到我的数据库时遇到了问题，我似乎无法找到我遇到的错误的答案

 System.MissingMethodException: Method not found: 'System.Data.Entity.Migrations.Builders.TableBuilder`1 System.Data.Entity.Migrations.Builders.TableBuilder`1.Index(System.Linq.Expressions.Expression`1>, Boolean, Boolean, System.Object)'.
   at Evento.Migrations.initialcreate.Up()
   at System.Data.Entity.Migrations.DbMigrator.ApplyMigration(DbMigration migration, DbMigration lastMigration)
   at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.ApplyMigration(DbMigration migration, DbMigration lastMigration)
   at System.Data.Entity.Migrations.DbMigrator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   at System.Data.Entity.Migrations.Infrastructure.MigratorLoggingDecorator.Upgrade(IEnumerable`1 pendingMigrations, String targetMigrationId, String lastMigrationId)
   at System.Data.Entity.Migrations.DbMigrator.UpdateInternal(String targetMigration)
   at System.Data.Entity.Migrations.DbMigrator.c__DisplayClassc.b__b()
   at System.Data.Entity.Migrations.DbMigrator.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.EnsureDatabaseExists(Action mustSucceedToKeepDatabase)
   at System.Data.Entity.Migrations.DbMigrator.Update(String targetMigration)
   at System.Data.Entity.Migrations.Infrastructure.MigratorBase.Update(String targetMigration)
   at System.Data.Entity.Migrations.Design.ToolingFacade.UpdateRunner.Run()
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.AppDomain.DoCallBack(CrossAppDomainDelegate callBackDelegate)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Run(BaseRunner runner)
   at System.Data.Entity.Migrations.Design.ToolingFacade.Update(String targetMigration, Boolean force)
   at System.Data.Entity.Migrations.UpdateDatabaseCommand.c__DisplayClass2.b__0()
   at System.Data.Entity.Migrations.MigrationsDomainCommand.Execute(Action command)
Method not found: 'System.Data.Entity.Migrations.Builders.TableBuilder`1 System.Data.Entity.Migrations.Builders.TableBuilder`1.Index(System.Linq.Expressions.Expression`1>, Boolean, Boolean, System.Object)'. 

Answer 1

我遇到了同样的问题，下面是我的解决方法。我希望这对其他人有帮助。

1. 我从我的引用中删除了 Entity Framework，并从我的 package.config 文件中删除了这些行。
2. 关闭 Visual Studio 并删除项目文件夹中的所有 EntityFramework DLL 文件
3. 打开 Visual Studio，然后进行清理和构建
4. 重新安装 Entity Framework
5. 重新清理并构建

在那之后，它开始工作了。