对Symbol的获取（Roslyn）

string s = @"class C { void M() {      } }";

SyntaxTree tree = SyntaxFactory.ParseSyntaxTree(text);

CSharpCompilation Compilation = CSharpCompilation
                .Create("test")
                .AddSyntaxTrees(tree)
                .AddReferences(MetadataReference.CreateFromFile(typeof(object).Assembly.Location));

  ///为了得到SemanticModel
SemanticModel semantic = Compilation.GetSemanticModel(tree);

//将树种的节点通过SemanticModelde得到Symbol
       SyntaxNode syntaxNode;
       tree.TryGetRoot(out syntaxNode);
       //这个方法在下面的片段里
       GetSymbolType(syntaxNode,semantic);  
public static void GetSymbolType(SyntaxNode node,SemanticModel model)
        {
            foreach (var item in node.DescendantNodesAndSelf().OfType<MemberDeclarationSyntax>())
            {
                //注意 GetDeclaredSymbol方法得到的传入的参数节点是
                //MemberDeclarationSyntax的子类，可以查看它都有哪些重载
                
                ISymbol type = model.GetDeclaredSymbol(item);
                
            }
        }