static void Main(string[] args)

  {

             var code = @"

     using System;

     public class _RoslynCodeCompletionSample

     {

         public void MyMethod()

         {

             var datetime = DateTime.Now;

             datetime.

         }

     }";

             //Microsoft.CodeAnalysis.CSharp namespace

             var syntaxTree = CSharpSyntaxTree.ParseText(code);

             //引入 DateTime 需要的程序集

             var cscompilation =CSharpCompilation.Create("_RoslynCodeCompletionSample")

                 .AddReferences(MetadataReference.CreateFromAssembly(typeof(DateTime).Assembly))

                 .AddSyntaxTrees(syntaxTree);

             var semanticModel = cscompilation.GetSemanticModel(syntaxTree);

             //获取代码提示 datetime.中.的TextSpan对象

             string codeIndex = "datetime.";

             var dotTextSpan = new TextSpan(code.IndexOf(codeIndex) + codeIndex.Length-, );

             var memberAccessNode = (MemberAccessExpressionSyntax)syntaxTree.GetRoot()

                 .DescendantNodes(dotTextSpan).Last();

             //获取类型信息

             var lhsType = semanticModel.GetTypeInfo(memberAccessNode.Expression).Type;

             //获取代码提示的内容

             foreach (var symbol in lhsType.GetMembers())

             {

                 if (!symbol.CanBeReferencedByName

                     || symbol.DeclaredAccessibility != Accessibility.Public

                     || symbol.IsStatic)

                     continue;

                 Console.WriteLine(symbol.Name);

             }

             Console.ReadLine();

 }