Fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware [0]

Question

While my .NET Core application is running, I noticed the following line:

fail: Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware[0]
      An unhandled exception has occurred: Method 'Clone' in type 'Microsoft.EntityFrameworkCore.Infrastructure.Internal.SqlServerOptionsExtension' from assembly 'Microsoft.EntityFrameworkCore.SqlServer, Version=1.1.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60' does not have an implementation. System.TypeLoadException: Method 'Clone' in type 'Microsoft.EntityFrameworkCore.Infrastructure.Internal.SqlServerOptionsExtension' from assembly 'Microsoft.EntityFrameworkCore.SqlServer, Version=1.1.2.0, Culture=neutral, PublicKeyToken=adb9793829ddae60' does not have an implementation.

I'm just wondering what causes this error because my applications are still working fine despite the error message.

By the way, I am using the version of .NET Core 2.0.0 Preview 1.

Answer 1

Microsoft.AspNetCore.Diagnostics.ExceptionHandlerMiddleware is only an intermediate infection, eliminating exceptions when there was nothing else in your program

So your “real” exception is this Method 'Clone' in type 'Microsoft.EntityFrameworkCore.Infrastructure.Internal.SqlServerOptionsExtension' from assembly 'Microsoft.EntityFrameworkCore.SqlServer,...' does not have an implementation

, , , .Net Core EF

, :

• https://docs.microsoft.com/en-us/aspnet/core/fundamentals/error-handling?view=aspnetcore-2.1#the-developer-exception-page
• EF (https://docs.microsoft.com/en-us/aspnet/core/fundamentals/logging/?view=aspnetcore-2.1#add-providers => enable , )