Get Roslyn SyntaxToken from Visual Studio Text Selection (caret position)

Question

I am attempting to bridge between the VSSDK and Roslyn SDK in a Visual Studio extension package and have been having a hard time with this. The ActivePoint.AbsoluteCharOffse

Answer 1

I'd highly recommend using Microsoft.VisualStudio.Text.SnapshotPoint from a Microsoft.VisualStudio.Text.Editor.IWpfTextView buffer instead of EnvDTE interfaces to interact with Roslyn.

Main code may look like this:

Microsoft.VisualStudio.Text.Editor.IWpfTextView textView =
    GetTextView();

Microsoft.VisualStudio.Text.SnapshotPoint caretPosition =
    textView.Caret.Position.BufferPosition;

Microsoft.CodeAnalysis.Document document =
    caretPosition.Snapshot.GetOpenDocumentInCurrentContextWithChanges();

Microsoft.CodeAnalysis.CSharp.Syntax.InvocationExpressionSyntax invocationExpressionNode = 
    document.GetSyntaxRootAsync().Result.
        FindToken(caretPosition).Parent.AncestorsAndSelf().
        OfType<Microsoft.CodeAnalysis.CSharp.Syntax.InvocationExpressionSyntax>().
        FirstOrDefault();

See Create a typed variable from the current method invocation for a complete example.