WF Activity得到Variable and Argument

 public sealed class CustomActivity1 : NativeActivity
    {
        protected override void Cancel(NativeActivityContext context)
        {
            Console.Write("Cancel");
            base.Cancel(context);
        }

        protected override void Abort(NativeActivityAbortContext context)
        {
            Console.Write("Abort");
            base.Abort(context);
        }


        protected override void CacheMetadata(NativeActivityMetadata metadata)
        {
            _locationReferences =
                metadata.Environment.GetLocationReferences().ToList();

            base.CacheMetadata(metadata);
        }

        protected override void Execute(NativeActivityContext context)
        {
            LocationReference locationReference =
                _locationReferences.Find(
                    x => x.Name == "Test" && x.Type == typeof(int));

            if (locationReference != null)
            {
                Console.WriteLine(
                    locationReference.Name + " " + locationReference.Type);

                // Blows up here.
                Location location = locationReference.GetLocation(context);
                location.Value = 5;
            }
          //  var pi = context.GetType().GetProperty("AllowChainedEnvironmentAccess", BindingFlags.NonPublic | BindingFlags.Instance);
          //  pi.SetValue(context, true, null);
            string myVaraibleName = "varaibleX";
            string myArgumentName = "argument1";

            string MyVariableValue = context.DataContext.GetProperties()[myVaraibleName].GetValue(context.DataContext).ToString();
            string myArgument = context.DataContext.GetProperties()[myArgumentName].GetValue(context.DataContext).ToString();
            Console.Write("Execute");
            var extension = context.GetExtension<MyExtension>();

        }

        private List<LocationReference> _locationReferences;


    }

    class MyExtension : IWorkflowInstanceExtension
    {
        private WorkflowInstanceProxy _instance;
        public IEnumerable<object> GetAdditionalExtensions()
        {
            return null;
        }
        public void SetInstance(WorkflowInstanceProxy instance)
        {
            _instance = instance;
        }
        public void WaitSome(Bookmark bookmark)
        {

            //  _instance.WorkflowDefinition

        }
    }