运行代码第一次迁移update-database时出错

Question

Im having trouble with my migration to my database and i can't seem to find a answer to the error i am getting

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

I ran into this same issue and here is how I resolved it. I hope this helps someone else.

1. I deleted Entity Framework from my References and removed the lines from my package.config file(s).
2. Closed Visual Studio and deleted all the EntityFramework DLL files in my project folders
3. Opened Visual Studio, then did a Clean and Build
4. Re-install Entity Framework
5. Did a Clean and Build again

After that, it was working.

Answer 2

This can also happen if Entity Framework is included in a referenced project but not in the project from where you are initializing the migration. Solution is to include EF in that project as well.

Answer 3

如果使用EF 6.2.0对新的dll运行旧版本的migrate.exe ，则会发生这种情况

Answer 4

如果您使用的是EF 6.1，则需要为Visual Studio 2013安装更新2

Answer 5

I ran into this error when running db.Database.Initialize(true); . I discovered that my the console app was referencing EF v 6.0, but the project with the DataContext and ModelBuilder were 6.1.3.

The error went away after setting the console app to 6.1.3 to match the others.