从 Visual Studio 文本选择（插入符号位置）获取 Roslyn SyntaxToken

Question

我试图在 Visual Studio 扩展包中的 VSSDK 和 Roslyn SDK 之间架起一座桥梁，但我一直很难做到这一点。 Visual Studio 提供的 ActivePoint.AbsoluteCharOffset 与我在使用 FindToken(offset) 时从 Roslyn 获得的元素不匹配。我相当确定这与每一方如何根据我当前的工作技巧计算 EOL 字符有关，但我并不是 100% 地认为我的技巧能够长期坚持下去。

我的 hack 是这一行：charOffset += point.Line;

我将行数添加到 char 偏移量上，这似乎可行，所以我猜我正在添加所有被活动点计数忽略的换行符。

帮手

private VisualStudioWorkspace workspace = null;
public RoslynUtilities(VisualStudioWorkspace workspace)
{
    this.workspace = workspace;
}
public Solution Solution { get { return workspace.CurrentSolution; } }
public Document GetDocumentFromPath(string fullPath)
{
    foreach (Project proj in this.Solution.Projects)
    {               
        foreach (Document doc in proj.Documents)
        {
            if (doc.FilePath == fullPath)
                return doc;                   
        }
    }
    return null;
}
public SyntaxTree GetSyntaxTreeFromDocumentPath(string fullPath)
{
    Document doc = GetDocumentFromPath(fullPath);
    if (doc != null)
        return doc.GetSyntaxTreeAsync().Result;
    else
        return null;
}
public SyntaxNode GetNodeByFilePosition(string fullPath, int absoluteChar)
{
    SyntaxTree tree = GetSyntaxTreeFromDocumentPath(fullPath);
    if(tree != null)
    {
        var compUnit = tree.GetCompilationUnitRoot();
        if(compUnit != null)
        {
            return compUnit.FindToken(absoluteChar, true).Parent;
        }
    }
    return null;                        
}
private VisualStudioWorkspace GetRoslynWorkspace()
    {
        var componentModel = (IComponentModel)GetGlobalService(typeof(SComponentModel));
        return componentModel.GetService<VisualStudioWorkspace>();
    }

主要部分

EnvDTE80.DTE2 applicationObject = (EnvDTE80.DTE2)GetService(typeof(SDTE));
EnvDTE.TextSelection ts = applicationObject.ActiveWindow.Selection as EnvDTE.TextSelection;
if (ts == null)
    return;

EnvDTE.VirtualPoint point = ts.ActivePoint;
int charOffset = point.AbsoluteCharOffset;
charOffset += point.Line;//HACK ALERT

Parse.Roslyn.RoslynUtilities roslyn = new Parse.Roslyn.RoslynUtilities(GetRoslynWorkspace());
SyntaxNode node = roslyn.GetNodeByFilePosition(applicationObject.ActiveDocument.FullName, charOffset);

Answer 1

我强烈建议使用 Microsoft.VisualStudio.Text.Editor.IWpfTextView 缓冲区中的 Microsoft.VisualStudio.Text.SnapshotPoint 而不是 EnvDTE 接口与 Roslyn 交互。

主代码可能如下所示：

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();

完整示例请参见Create a typed variable from the current method invocation。