运行dnx ef迁移时出错，添加Initial

Question

在visual studio 2015中，当我运行DNX命令在DB中创建表时，我收到错误。有什么帮助吗？

c:\Visual Studio Projects\MVAMVC\src\MVAMVC>dnx ef migrations add Initial
System.MissingMethodException: Method not found: 'Void Microsoft.Extensions.Logging.LoggerExtensions.LogVerbose(Microsoft.Extensions.Logging.ILogger, System.String)'.
   at Microsoft.Data.Entity.Commands.Program.Executor.LogException(Exception ex)
   at Microsoft.Data.Entity.Commands.Program.Executor.Execute(Action action)
   at Microsoft.Data.Entity.Commands.Program.Executor.AddMigration(String name, String outputDir, String context)
   at Microsoft.Data.Entity.Commands.Program.<>c__DisplayClass2_7.<Main>b__15()
   at Microsoft.Dnx.Runtime.Common.CommandLine.CommandLineApplication.Execute(String[] args)
   at Microsoft.Data.Entity.Commands.Program.Main(String[] args)
--- End of stack trace from previous location where exception was thrown ---
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at Microsoft.Dnx.Runtime.Common.EntryPointExecutor.Execute(Assembly assembly, String[] args, IServiceProvider serviceProvider)
   at Microsoft.Dnx.ApplicationHost.Program.<>c__DisplayClass3_0.<ExecuteMain>b__0()
   at System.Threading.Tasks.Task`1.InnerInvoke()
   at System.Threading.Tasks.Task.Execute()