In Java we have used the javaagent argument and ASM (http://asm.ow2.org/) utilities to modify the byte code at run/load time in memory by the classloader . (aka Add a method call to a method in a class dynamically).
Once example of this is where you remove all calls to Log4j to speed up an application (http://surguy.net/articles/removing-log-messages.xml).
I’m trying to figure out how to do this same process on runtime with C# / .Net. I have seen that you can manipulate the CIL for .Net, but I haven’t found an example of this at runtime.
System.Reflection.Emit seems to be the closest .Net equitant where you can dynamically create classes, but is there a way to add to or override existing classes using this?