C＃类向后兼容性规则/避免中断更改

I'm working on a C# 3.5 assembly that is consumed by many different applications in an enterprise server environment. I would like to add some properties to an existing C# class (not abstract) and maintain backwards compatibility with current clients without recompiling. It’s a strongly named 3.5 assembly. Existing client applications will not be recompiled. Instead we use publisher policy assemblies to re-direct existing clients to the updated version.I'm working on a C# 3.5 assembly that is consum