ILSpy is a free and open-source .NET assembly browser and decompression tool that is pretty popular in the C# development field, developed by ICSharpCode (i.e. the development team of SharpDevelop). It has the user interface, layout, and decompilation functions similar to Red Gate Software's .NET Reflector. Moreover, sometimes for some assemblies that can not be decompiled with .NET Reflector (because of encryption), it's still possible to do that using ILSpy. Simply speaking, it has only one purpose - to finally completely replace .NET Reflector and do better.

It is worth mentioning that ILSpy, as a decompression software specially built for.NET programs, itself is also written in C#, supports fast and stable decompression of C# and VB, comes with very comprehensive and efficient decompression functions, and is easy to use and portable. In addition, it is able to convert a DLL file into C# or VB language, saves individual file as .cs or .vb format, allows to save multiple files as a project file, even can disassemble the internal code of unknown assemblies.

ILSpy was born because the excellent decompiler .NET Reflector announced that it would no longer be available for free after February 2011 (but AppNee will continue to provide its commercial editions). In other words, Red Gate Software's decision doubtlessly spawned this open-source project ILSpy, which became its own strong rival. Also, if Red Gate Software could not make .NET Reflector become far ahead of ILSpy, then its time to live is running out fast.

Key Features

  • Decompilation to C#
  • Whole-project decompilation (csproj, not sln!)
  • Search for types/methods/properties (substring)
  • Hyperlink-based type/method/property navigation
  • Base/Derived types navigation, history
  • BAML to XAML decompiler
  • Extensible via plugins (MEF)
  • Check out the language support status

System Requirements

  • Microsoft .NET Framework 4.0

Download URLs

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