找到属于InvocationExpressionSyntax的usingdirectivessyntax

本文关键字：usingdirectivessyntax InvocationExpressionSyntax 属于 | 更新日期: 2023-09-27 18:06:35

在下面的代码中，WriteLine"调用需要"System" using指令才能工作。我已经有一个UsingDirectiveSyntax对象"使用系统"和一个InvocationExpressionSyntax对象"Console.Writeline"。但是我怎么知道，使用Roslyn, InvocationExpressionSyntax和usingdirectivessyntax对象属于彼此?

using System;       
public class Program
{
   public static void Main()
   {
      Console.WriteLine("Hello World");
   }
}

InvocationExpressionSyntax的方法符号有一个成员ContainingNamespace，该成员应该等于您从检索using指令的符号中获得的名称空间符号。这里的技巧是使用Name成员作为查询语义模型的起点，因为整个UsingDirectiveSyntax不会给您一个符号。

尝试这个LINQPad查询(或将其复制到控制台项目中)，您将在查询的最后一行得到true;)

// create tree, and semantic model
var tree = CSharpSyntaxTree.ParseText(@"
    using System;
    public class Program
    {
       public static void Main()
       {
          Console.WriteLine(""Hello World"");
       }
   }");
var root = tree.GetRoot();
var mscorlib = MetadataReference.CreateFromFile(typeof(object).Assembly.Location);
var compilation = CSharpCompilation.Create("SO-39451235", syntaxTrees: new[] { tree }, references: new[] { mscorlib });
var model = compilation.GetSemanticModel(tree);
// get the nodes refered to in the SO question
var usingSystemDirectiveNode = root.DescendantNodes().OfType<UsingDirectiveSyntax>().Single();
var consoleWriteLineInvocationNode = root.DescendantNodes().OfType<InvocationExpressionSyntax>().Single();
// retrieve symbols related to the syntax nodes
var writeLineMethodSymbol = (IMethodSymbol)model.GetSymbolInfo(consoleWriteLineInvocationNode).Symbol;
var namespaceOfWriteLineMethodSymbol = (INamespaceSymbol)writeLineMethodSymbol.ContainingNamespace;
var usingSystemNamespaceSymbol = model.GetSymbolInfo(usingSystemDirectiveNode.Name).Symbol;
// check the namespace symbols for equality, this will return true
namespaceOfWriteLineMethodSymbol.Equals(usingSystemNamespaceSymbol).Dump();