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AvalonEdit is the WPF-based text editor used in SharpDevelop. There are five builds of AvalonEdit included in this package: .NET Framework 4.5 and 4.0, .NET Core 3.1, .NET 5.0 for Windows, .NET 6.0 for Windows.

ICSharpCode.Decompiler is the decompiler engine used in ILSpy.

NRefactory supports analysis of C# source code: it includes a parser, abstract syntax tree, type system, semantic analysis (resolver), code completion, and several refactorings.

Sample code for AvalonEdit the WPF-based text editor used in SharpDevelop. Modify your App.xaml file so the StartupUri points to the AvalonEdit Sample window: StartupUri="/Samples/AvalonEdit/Window1.xaml"