Question

我已经启用了迁移：

enable-Migrations -ProjectName ProjectOne -ContextTypeName MyIdentity.Config.MyIdentityContext -MigrationsDirectory Identity\\Migrations

我指定了我的上下文，因为它位于一个独立的命名空间中，我指定了该目录，因为我希望将迁移放在另一个目录中。

启用此类迁移后，我在预期位置（Identity \ Migrations文件夹）中获取预期的配置文件（我删除了种子过程中的注释）

Friend NotInheritable Class Configuration
    Inherits DbMigrationsConfiguration(Of MyIdentityDbContext)

    Public Sub New()
        AutomaticMigrationsEnabled = False
        MigrationsDirectory = "Identity\\Migrations"
    End Sub

    Protected Overrides Sub Seed(context As MyIdentityDbContext)

    End Sub

End Class

在此之后我创建了一个迁移：

add-migration Initial

但后来我收到一条错误，指出该文件已经存在：

Scaffolding migration 'Initial'.
System.Runtime.InteropServices.COMException (0x80040400): Unable to add '201506111233565_Initial.vb'. A file with that name already exists.

Server stack trace: 
at EnvDTE.ProjectItems.AddFromFileCopy(String FilePath)
at System.Runtime.Remoting.Messaging.StackBuilderSink._PrivateProcessMessage(IntPtr md, Object[] args, Object server, Object[]& outArgs)
at System.Runtime.Remoting.Messaging.StackBuilderSink.SyncProcessMessage(IMessage msg)

Exception rethrown at [0]: 
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg)
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type)
at EnvDTE.ProjectItems.AddFromFileCopy(String FilePath)
at System.Data.Entity.Migrations.Extensions.ProjectExtensions.AddFile(Project project, String path)
at System.Data.Entity.Migrations.Extensions.ProjectExtensions.AddFile(Project project, String path, String contents)
at System.Data.Entity.Migrations.Utilities.MigrationWriter.Write(ScaffoldedMigration scaffoldedMigration, Boolean rescaffolding, Boolean force, String name)
at System.Data.Entity.Migrations.AddMigrationCommand.WriteMigration(String name, Boolean force, ScaffoldedMigration scaffoldedMigration, Boolean rescaffolding)
at System.Data.Entity.Migrations.AddMigrationCommand.Execute(String name, Boolean force, Boolean ignoreChanges)
at System.Data.Entity.Migrations.AddMigrationCommand.<>c__DisplayClass2.<.ctor>b__0()
at System.Data.Entity.Migrations.MigrationsDomainCommand.Execute(Action command)
Unable to add '201506111233565_Initial.vb'. A file with that name already exists.

当我查看解决方案资源管理器时（刷新后）文件就在那里，但是从项目中排除。

当我删除MigrationsDirectory =“Identity \ Migrations”时，它运行正常（但正在\ Migrations中创建迁移文件）

我不认为这是相关的，但要确定：我也在使用Team explorer 2013对此项目进行源代码控制。

Answer 1

您的文件夹名称格式错误，因此EF认为它是一个文件。尝试在此处使用单个反斜杠：-MigrationsDirectory Identity\Migrations而不是-MigrationsDirectory Identity\\Migrations

添加迁移使文件名已存在

1 个答案: