ILSpy 9.x is based on .NET 8.0. All artifacts except the self-contained distribution are built framework-dependent, which means .NET 8.0.x or later must be installed prior to starting ILSpy. Note that ILSpy 9.1 also allows a later runtime via [#3391].

New Language Features

• Update pattern-detection to Roslyn 4.13

Enhancements

• [#1572]: Do not generate variable names that match C# keywords.
• [#2716]: Add an option to allow sorting custom attributes
• [#3377]: Extend error information if multiple assemblies with the same (short) name are selected when creating a solution file.
• [#3393]: Option to turn off smooth scrolling
• [#3399]: Add module filename as ToolTip of AnalyzerEntityTreeNode
• [#3440]: Added support for evaluation-order-preserving reference type check
• [#3316]: Add "variable scopes" to improve naming local variables and anonymous method parameters

Contributions

• Add support for array initialization based on RuntimeHelpers.CreateSpan<T> (see [#3380] by @ds5678)
• Load resource stream outside of delegate (see [#3389] by @snorrk)
• Allow ILSpy to launch, when net8.0 is not installed, but a later version (see [#3391] by @nil4)
• Fix nested namespace directories (see [#3449] by @ds5678)
• Fix [#3402]: System.NullReferenceException on right click on .NET 9 (see [#3403] by @tom-englert)
• Add an option to turn off smooth scrolling (see [#3405] by @tom-englert)
• Use type hint in pointer arithmetic (see [#3413] by @ds5678)
• Improve UI for primary constructors on non-record types (see [#3455] by @ds5678)
• Fix exception when writing resx files without adding any resources (see [#3418] by @jwfx)
• Enhance null handling in switch transformations (see [#3422] by @ds5678)
• Don't include generic constraints in generated explicit overrides (see [#3443] by @ds5678)
• Improve generation of not equals check (see [#3425] by @ElektroKill)

Bug fixes

• Fix [#2269]: LocalFunctionDecompiler misplaces nested local functions in ctors
• Fix [#3322]: Add missing checks for equality comparison
• Fix [#3378]: Navigation shortcuts (Alt-Left and Alt-Right) don't work when TreeView has focus
• Fix [#3381]: Make sure that selectedNode is still selected when focus is deferred in IsActive property changed handler.
• Fix [#3383]: more aggressively transform object initializers on structs
• Fix [#3384]: add special case for null-literal conversions in optional argument handling.
• Fix [#3385]: Allow address uses of structs in using transform, if the reference is passed to an in parameter.
• Fix [#3392]: uses of init-setters must use object-initializer syntax.
• Fix [#3401]: Multiple problems when exporting an assembly as project
• Fix [#3414]: Apply latest session settings before saving upon closing the main window
• Fix [#3342]: Wrong null check in MethodVirtualUsedByAnalyzer
• Fix [#3450]: Fix "Clear assembly list" not actually persistent.
• Fix [#3432]: Do not include delegate construction use-sites in DetermineCaptureAndDeclarationScopes.
• Fix attributes tooltip of GenericParam metadata table

And many other fixes, for a full list click here.