ILSpy
MIT🧬 Reverse Engineering · C#
ILSpy is the open-source .NET assembly browser and decompiler. It supports decompilation of .NET assemblies to C# with high-quality output, including support for modern C# features like async/await, LINQ, and pattern matching. ILSpy can decompile entire assemblies or individual types and members, with the ability to search across loaded assemblies and navigate type hierarchies. It supports .NET Framework, .NET Core, .NET 5+, and Mono assemblies. Unlike dnSpy, ILSpy focuses purely on decompilation and browsing rather than debugging and editing, making it lighter and more focused. It's available as a standalone Windows application, a VS Code extension, and a command-line tool (ilspycmd) for cross-platform use. ILSpy is actively maintained and is the most widely used open-source .NET decompiler.
Installation
Chocolatey
$ choco install ilspyCLI (cross-platform)
$ dotnet tool install ilspycmd -gVS Code Extension
$ Install 'ilspy-vscode' from VS Code marketplaceUse Cases
- Decompiling .NET assemblies to readable C# for code review or analysis
- Browsing type hierarchies and dependencies in compiled .NET libraries
- Cross-platform decompilation using the ilspycmd command-line tool
- Searching for specific strings, types, or methods across loaded assemblies
- Comparing decompiled output across different .NET framework versions
Tags
Details
- Category
- 🧬 Reverse Engineering
- Language
- C#
- Repository
- icsharpcode/ILSpy
- License
- MIT
- Platforms
- 🪟windows🐧linux🍎macos
Links
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dnSpy
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x64dbg
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