问题
Does anyone here has experience with IBM.EntityFrameworkCore package? I've created a .NET Standard 2.0 library project in VS2017, added mentioned package, and tried to make it work by following this and this tutorial from IBM website, with no luck. I get the project compiled, but at the runtime I'm getting a System.TypeLoadException with the following message:
Method 'ApplyServices' in type 'IBM.EntityFrameworkCore.Infrastructure.Internal.Db2OptionsExtension' from assembly 'IBM.EntityFrameworkCore, Version=1.1.1.101, Culture=neutral, PublicKeyToken=7c307b91aa13d208' does not have an implementation.
Any help will be appreciated!
Thanks!
Update: The exception happens as soon as I try to use the context. It means after the context is successfully created, but before DbContext.OnConfiguring call happens.
回答1:
I've solved it. It turned out that this exception happens if actual entity types (i.e. MyType) aren't defined in the same assembly (project) as the context. In my solution I had entity types defined in one project, and DbContextdefined in a different project, that references the first one, of course.
The reason for me to have such design was in the fact that there are two different packages (depending on the actual OS): IBM.EntityFrameworkCore and IBM.EntityFrameworkCore-lnx. So I've created two different projects, each referencing one of these packages. Still, I wanted to have all the entity types defined once... But obviously it cannot work like that.
Update: Sadly, it turned out that this isn't the only issue. I've ran into another one, described here. Thumbs down for DB2 .NET team! It's always frustrating to work with...
来源：https://stackoverflow.com/questions/45782871/net-standard-2-0-entityframeworkcore-db2-ibm-entityframeworkcore-issue