运行代码第一次迁移update-database时出错

Question

我无法迁移到我的数据库,我似乎找不到我得到的错误的答案

 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,这就是我如何解决它.我希望这有助于其他人.

1. 我从我的References中删除了Entity Framework,并从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,然后执行Clean和Build
4. 重新安装实体框架
5. 做了一个清洁和再次构建

在那之后,它正在运作.

Answer 2

如果实体框架包含在引用的项目中，但不包含在您初始化迁移的项目中，也可能会发生这种情况。解决方案是将 EF 也包含在该项目中。