Although there are many similar tools available, ILSpy is very easy to use as well as free and open-source. It doesn’t require any installation, which means it can be saved to your portable application collection, copied to a USB flash drive, and can be used on any PC without setup to browse and inspect .NET assemblies.

Software features:

Use this tool to take a closer look. The .NET Assembly
main application window has a clear layout and is divided into two main panes: for navigating the .NET assembly tree and for taking a closer look at any selected items. It can check DLL, EXE, and WINMD files (Windows metadata). You can load data from the GAC or open a Nuget package.

ILSpy has the ability to render code in C#, IL, and IL using C#. For C#, you can choose C# 1.0/VS .NET to C# 7.2/VS 2017. For example, you can view resources and references, view tables, and extract information to a file.

Rendering code in C#, IL, and IL
using C# Since the program is for viewing purposes only, file modifications are not possible. On the other hand, you can take advantage of the search function when looking for type, member, method, field, property, event, constant, or metadata tags.

You can configure several decompiler settings, such as using variable names in debug symbols, removing code that has no dead zones and side effects, or extending member definitions after decompilation. In addition, you can customize the font and allow multiple instances.

All things considered, IlSpy makes it as simple as possible to decompile .NET assemblies and see what makes the software simple. Since it is open-source, developers are free to modify and use their code as they please.

Changelog

New Language Features

• Updated pattern detection to Roslyn 4.12

Contributions

• Diagramming feature
• More WPF-related refactorings
• High DPI fixes
• Missing DecompilerSetting

Enhancements

• Allow implicit conversions in switch

Performance

• Performance: Initialize ToolPanes in instead of the property getter to avoid WPF seeing them in and rendering all panes docked at the right before the layout is properly initialized.DockWorkspace.InitializeLayout()InitializeComponent()

Bug fixes

• Fix #3319: KeyDownEvent field reference was replaced with KeyDown event reference.
• Fix #3349: Make ILSpy ready for .NET 10
• Fix #3361: switch-value conversion was losing its target type.

Download link . Net decompile ILSpy