I needed to compare two assemblies the other day. More specifically, in a project my team works on, we use a custom version of the AjaxToolkit and I wanted to track down the changes.
.NET Reflector
My first though went to .NET Reflector. Reflector is A CLR class browser with XML documentation viewer, type search, disassembler and C#/VB view. Reflector is extendable via add-ins and after searching a bit on the net, I found Diff, that does pretty much what is says, that is compare two assemblies and view the differences between them.
Unfortunately I did not have any luck getting Diff to work, because the tool detected that the assembly against which I’m comparing is the same with the assembly that gets compared. That makes sense, because in the custom assembly we did not change any assembly metadata, just code.
Framework Design Studio
Some more research on the net, revealed me a wonderful piece of code after the name Framework Design Studio, which did exactly what I was looking for, that is view, review, and compare versions of managed APIs.
I tested it against our custom AjaxToolkit assembly and it happily found all the managed differences with the original one and I was able to export the differences in a Word document.
As the tool name suggests, it didn’t find the differences in the JavaScript files or any other resources.
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