How can I programatically (using reflection?) change a method body and save my changes back to disk

Question

I can get at the method body easily enough using reflection

Type type = assembly.GetType("Lorem.Ipsum.Dolor.Sit");
MethodInfo methodInfo = type.GetMethod("Amet");
MethodBody methodBody = methodInfo.GetMethodBody();

How can I programatically change the method body and save my changes back to disk?

Answer 1

AFAIK, you can't.

With reflection you modified an in-memory object which was produced from a binary loaded and optimized by the CLR at runtime.

EDIT

This question has some more information on this.

Modifying Existing .NET Assemblies

Answer 2

One another good lib for this: https://bitbucket.org/0xd4d/dnlib

Handles obfuscated assemblies much better comparing to Mono.Cecil.