First of all, this test is not successful, it is only feasible on this machine, and the test fails on different machines. The GUID may be incorrect or not registered successfully.
Now that we've spent the whole morning studying, I'm going to summarize
1. Online said to create an SNK certificate, but not created or can. Just can't put it in the GAC. It seems to be placed in the file's current directory as well. (GAC is a general DLL directory similar to System32, which corresponds to the DLL to be found through the UUID)
The 2.tlb file resembles a header file, and the compile phase obtains the function interface. This file is not required when compiling.
3.ClassInterface (classinterfacetype.autodual)] can be used instead of generating an additional interface. Look at this blog post specifically
4. The rest can refer to some of the online C # output COM articles
5. To compare the UUID, please refer to this section
A summary of the COM way to implement C + + calling C # code