Compare compiled .NET assemblies?

Question

Are there any good programs out there to compare to compile .NET assemblies?

For example I have HelloWorld.dll (1.0.0.0) and HelloWorld.dll (2.0.0.0), and I want to compare differences how can I do this?

I know I can use .NET Reflector and use the Assembly Diff plugin. Are there any other good tools out there to do this?

Answer 1

Two ways.

You could ILDASM and diff with classic tools.

Or you could use NDepends, which will cost for that feature.

[Piece to C# bloaters..]

Answer 2

Ways to Compare .NET Assemblies suggests

Commercial:

• NDepend
• BitDiffer

Free:

• Reflector Diff Add-in (which you've already discovered)
• Framework Design Studio

Answer 3

Java has a nice one: http://stackoverflow.com/questions/523307/semantic-diff-utilities/

Answer 4

I just had to compare two revisions of the same DLL, which had the same version (I needed to implement a small hotfix, and deploy the DLL in production, but I wanted to make sure that no other changes leaked into code). Ideally, I would want the Assemby Diff add-in to show me the difference, but it does not work (it thinks that I'm comparing a DLL to itself). So this is what I did:

• Created two folders to hold disassembled source files.
• Used the Reflector's Export option (from context menu) to generate source files from each DLL in the folders created in previous step.
• Used the free DiffMerge tool to compare two directories; the tools showed me the modified files and the difference.

It's a bit kludgy, but seems to work. I wish the Assembly Diff add-in worked, though.

Answer 5

NDepend is really what you need to compare compiled .NET assemblies:

Step1: ask for changes (here ask for methods where code was changed or was added)

Step2: compare source code method bodies (if you have PDB files and source code),

Step2 Bis: compare 2 versions of the IL code of a method within one click (NDepend will use automation on Reflector for that).