How to decompile a C# .exe on macOS?

Question

It this even possible? Are there any free tools?

Did you try those https://github.com/aerror2/ILSpy-For-MacOSX or http://tirania.org/blog/archive/2011/Feb-04.html. — PhoeniX, May 15 '17 at 18:26
I did, but after i build the project and run the .exe with mono, i get an error. I get this: Unhandled Exception: System.NullReferenceException: Object reference not set to an instance of an object. I may debug the project in the future to find the issue if no easier solution will arise till then. :) — ttt, May 15 '17 at 18:43
It depends on the complexity of the original executable, but in general debugger is the way to solve the problem. — PhoeniX, May 15 '17 at 18:49

gandarez · Answer 1 · 2019-02-14T22:19:51.803

13

Visual Studio for Mac can do the job. Just hit File / Open and then choose the executable or library you want. It'll open the Assembly Browser window.

If you need more detailed code change the Visibility to All members and the Language to C#.

edited Feb 14 '19 at 22:19

answered Feb 13 '19 at 19:10

gandarez

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but this way doesn't give you the code. Only the signatures of the methods. – Paweł Łukasik Feb 13 '19 at 21:39
@PawełŁukasik yes you can do, just take a look at my updated post. – gandarez Feb 14 '19 at 22:20
Yup. My mistake. – Paweł Łukasik Feb 14 '19 at 22:24

Chris Tsiakoulas · Answer 2 · 2017-05-21T08:22:58.160

5

Best free tool for the job is ILSpy, but it runs on Windows. This gives you a limited list of options:

create a windows virtual machine (with virtualbox or vmware player) and run it in there
install WINE on mac, to allow you run .exe files.
get visual studio for mac and use ikdasm
if you feel hardcore, open it in a disassembler ;)

Being an IT guy myself, I would go for the first solution. Check them all out briefly and go for one!

edited May 21 '17 at 08:22

answered May 20 '17 at 14:12

Chris Tsiakoulas

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for point 3, there's no tool called ildasm. The tools that are included VS for Mac are called ikdasm or monodis – Paweł Łukasik May 21 '17 at 05:44
Thnks for the notice! I corected it. – Chris Tsiakoulas May 21 '17 at 08:23

jbarrameda · Answer 3 · 2018-03-15T12:41:34.727

2

You can use Jetbrains' Rider. It has a 30 day free trial period.

Open Rider and open or create a C# project
Add a dependency to the .exe file (naturally, this also works for .dll).

In a class in your project, import the package and type the class you want to inspect.

Do Command+click or Command+B on the class name to trigger Rider's decompile option. Confirm if necessary.

The disadvantage is that we have to repeat step 4 for each class we want to decompile.

edited Mar 15 '18 at 12:41

answered Mar 12 '18 at 20:41

jbarrameda

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it looks like you were too fast. Point 4 is incomplete and 5 is missing. – Paweł Łukasik Mar 13 '18 at 08:10

score 0 · Answer 4 · answered Mar 22 '24 at 14:57

Is this even possible?

Generally yes, with a couple of exceptions:

Starting with .NET Core and now .NET the .exe files produced by the compilation of applications are not CLR assemblies but native assemblies. CLR assemblies contain IL and are decompilable to C# while native assemblies contain machine code and cannot be decompiled to C#.

Hint: in that scenario one should decompile the .dll with the same name. That's the file that contains the compiled C# code.

Ahead-of-Time compiled .exe files are also not CLR assemblies and cannot be decompiled to C#

Are there any free tools?

Yes, there are. One such tool is CodemerxDecompile - the spiritual successor of the popular JustDecompile. While JustDecompile is Windows only, CodemerxDecompile is a multi-platform decompiler that runs on Windows, Linux and MacOS.

Disclosure: I'm part of the team behind CodemerxDecompile.

How to decompile a C# .exe on macOS?

4 Answers4