public class WriteObject : CodeActivity
    {
        [RequiredArgument]
        [DefaultValue(null)]
        public InArgument What { get; set; }

        protected override void Execute(CodeActivityContext context)
        {
            Console.WriteLine(this.What.Get(context));
        }

        protected override void CacheMetadata(CodeActivityMetadata metadata)
        {
            Collection<RuntimeArgument> arguments = new Collection<RuntimeArgument>();
            Type argumentType1 = typeof(object);
            if (this.What != null)
                argumentType1 = this.What.ArgumentType;
            RuntimeArgument runtimeArgument1 = new RuntimeArgument("What", argumentType1, ArgumentDirection.In, true);
            metadata.Bind((Argument)this.What, runtimeArgument1);
            arguments.Add(runtimeArgument1);
            metadata.SetArgumentsCollection(arguments);
        }
    }