Activate ViewDataDictionary in DefaultTagHelperActivator

src/Microsoft.AspNet.Mvc.Razor/DefaultTagHelperActivator.cs

@@ -43,17 +43,22 @@ namespace Microsoft.AspNet.Mvc.Razor
         private static PropertyActivator<ViewContext> CreateActivateInfo(PropertyInfo property)
         {
             Func<ViewContext, object> valueAccessor;
+            var propertyType = property.PropertyType;
 
-            if (property.PropertyType == typeof(ViewContext))
+            if (propertyType == typeof(ViewContext))
             {
                 valueAccessor = viewContext => viewContext;
             }
+            else if (propertyType == typeof(ViewDataDictionary))
+            {
+                valueAccessor = viewContext => viewContext.ViewData;
+            }
             else
             {
                 valueAccessor = (viewContext) =>
                 {
                     var serviceProvider = viewContext.HttpContext.RequestServices;
-                    var service = serviceProvider.GetRequiredService(property.PropertyType);
+                    var service = serviceProvider.GetRequiredService(propertyType);
 
                     var contextable = service as ICanHasViewContext;
                     contextable?.Contextualize(viewContext);

test/Microsoft.AspNet.Mvc.FunctionalTests/ActivatorTests.cs

@@ -187,6 +187,7 @@ namespace Microsoft.AspNet.Mvc.FunctionalTests
                            "<input id=\"foo\" name=\"foo\" type=\"hidden\" value=\"test content\" />" +
                            "</span>" +
                            Environment.NewLine +
+                           "<footer>Footer from activated ViewData</footer>" +
                            "</body>";
 
             // Act

test/Microsoft.AspNet.Mvc.Razor.Test/RazorPageCreateTagHelperTest.cs

@@ -56,6 +56,33 @@ namespace Microsoft.AspNet.Mvc.Razor
             Assert.NotNull(tagHelper.ViewContext);
         }
 
+        [Fact]
+        public void CreateTagHelper_ProvidesTagHelperWithViewData()
+        {
+            // Arrange
+            var instance = CreateTestRazorPage();
+
+            // Act
+            var tagHelper = instance.CreateTagHelper<ViewDataTagHelper>();
+
+            // Assert
+            Assert.NotNull(tagHelper.ViewData);
+        }
+
+        [Fact]
+        public void CreateTagHelper_ProvidesTagHelperWithInternalProperties()
+        {
+            // Arrange
+            var instance = CreateTestRazorPage();
+
+            // Act
+            var tagHelper = instance.CreateTagHelper<TagHelperWithInternalProperty>();
+
+            // Assert
+            Assert.NotNull(tagHelper.ViewData);
+            Assert.NotNull(tagHelper.ViewContext);
+        }
+
         [Fact]
         public void CreateTagHelper_ProvidesTagHelperTypeWithViewContextAndActivates()
         {
@@ -120,12 +147,27 @@ namespace Microsoft.AspNet.Mvc.Razor
             public ViewContext ViewContext { get; set; }
         }
 
+        private class ViewDataTagHelper : TagHelper
+        {
+            [Activate]
+            public ViewDataDictionary ViewData { get; set; }
+        }
+
         private class ViewContextServiceTagHelper : ViewContextTagHelper
         {
             [Activate]
             public MyService ActivatedService { get; set; }
         }
 
+        private class TagHelperWithInternalProperty : TagHelper
+        {
+            [Activate]
+            protected internal ViewDataDictionary ViewData { get; set; }
+
+            [Activate]
+            protected internal ViewContext ViewContext { get; set; }
+        }
+
         private class MyService
         {
         }

test/WebSites/ActivatorWebSite/TagHelpers/FooterTagHelper.cs

@@ -0,0 +1,24 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNet.Mvc;
+using Microsoft.AspNet.Mvc.Rendering;
+using Microsoft.AspNet.Razor.Runtime.TagHelpers;
+
+namespace ActivatorWebSite.TagHelpers
+{
+    [HtmlElementName("body")]
+    public class FooterTagHelper : TagHelper
+    {
+        [Activate]
+        public IHtmlHelper HtmlHelper { get; set; }
+
+        [Activate]
+        public ViewDataDictionary ViewData { get; set; }
+
+        public override void Process(TagHelperContext context, TagHelperOutput output)
+        {
+            output.PostContent = $"<footer>{HtmlHelper.Encode(ViewData["footer"])}</footer>";
+        }
+    }
+}

test/WebSites/ActivatorWebSite/Views/View/UseTagHelper.cshtml

@@ -5,6 +5,7 @@
 
 @{
     ViewBag.Title = "Activation Test";
+    ViewData["footer"] = "Footer from activated ViewData";
 }
 
 <body>