Add TempData property and some functional tests

src/Microsoft.AspNetCore.Mvc.RazorPages/Page.cs

@@ -2,13 +2,10 @@
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
 using System;
-using System.Collections.Generic;
 using System.Diagnostics;
-using System.Text.Encodings.Web;
-using Microsoft.AspNetCore.Html;
 using Microsoft.AspNetCore.Mvc.Razor;
-using Microsoft.AspNetCore.Mvc.Razor.Internal;
 using Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
+using Microsoft.AspNetCore.Mvc.ViewFeatures;
 using Microsoft.Extensions.DependencyInjection;
 
 namespace Microsoft.AspNetCore.Mvc.RazorPages
@@ -49,6 +46,12 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             }
         }
 
+        /// <summary>
+        /// Gets the <see cref="ITempDataDictionary"/> from the <see cref="PageContext"/>.
+        /// </summary>
+        /// <remarks>Returns null if <see cref="PageContext"/> is null.</remarks>
+        public ITempDataDictionary TempData => PageContext?.TempData;
+
         /// <inheritdoc />
         public override void EnsureRenderedBodyOrSections()
         {
@@ -90,5 +93,32 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             }
         }
 
+        /// <summary>
+        /// Creates a <see cref="RedirectResult"/> object that redirects to the specified <paramref name="url"/>.
+        /// </summary>
+        /// <param name="url">The URL to redirect to.</param>
+        /// <returns>The created <see cref="RedirectResult"/> for the response.</returns>
+        protected RedirectResult Redirect(string url)
+        {
+            if (string.IsNullOrEmpty(url))
+            {
+                throw new ArgumentException(Resources.ArgumentCannotBeNullOrEmpty, nameof(url));
+            }
+
+            return new RedirectResult(url);
+        }
+
+        /// <summary>
+        /// Creates a <see cref="PageViewResult"/> object that renders this page as a view to the response.
+        /// </summary>
+        /// <returns>The created <see cref="PageViewResult"/> object for the response.</returns>
+        /// <remarks>
+        /// Returning a <see cref="PageViewResult"/> from a page handler method is equivalent to returning void.
+        /// The view associated with the page will be executed.
+        /// </remarks>
+        protected PageViewResult View()
+        {
+            return new PageViewResult(this);
+        }
     }
 }

src/Microsoft.AspNetCore.Mvc.RazorPages/PageModel.cs

@@ -44,6 +44,12 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
 
         public ModelStateDictionary ModelState => PageContext.ModelState;
 
+        /// <summary>
+        /// Gets the <see cref="ITempDataDictionary"/> from the <see cref="PageContext"/>.
+        /// </summary>
+        /// <remarks>Returns null if <see cref="PageContext"/> is null.</remarks>
+        public ITempDataDictionary TempData => PageContext?.TempData;
+
         public ViewDataDictionary ViewData => PageContext?.ViewData;
 
         protected Task<T> BindAsync<T>(string name)

src/Microsoft.AspNetCore.Mvc.RazorPages/Properties/Resources.Designer.cs

@@ -74,6 +74,22 @@ namespace Microsoft.AspNetCore.Mvc.RazorPages
             return string.Format(CultureInfo.CurrentCulture, GetString("PageViewResult_ContextIsInvalid"), p0, p1);
         }
 
+        /// <summary>
+        /// Value cannot be null or empty.
+        /// </summary>
+        internal static string ArgumentCannotBeNullOrEmpty
+        {
+            get { return GetString("ArgumentCannotBeNullOrEmpty"); }
+        }
+
+        /// <summary>
+        /// Value cannot be null or empty.
+        /// </summary>
+        internal static string FormatArgumentCannotBeNullOrEmpty()
+        {
+            return GetString("ArgumentCannotBeNullOrEmpty");
+        }
+
         private static string GetString(string name, params string[] formatterNames)
         {
             var value = _resourceManager.GetString(name);

src/Microsoft.AspNetCore.Mvc.RazorPages/Resources.resx

@@ -129,4 +129,7 @@
   <data name="PageViewResult_ContextIsInvalid" xml:space="preserve">
     <value>Argument '{0}' is not the same instance used to create '{1}'.</value>
   </data>
+  <data name="ArgumentCannotBeNullOrEmpty" xml:space="preserve">
+    <value>Value cannot be null or empty.</value>
+  </data>
 </root>

test/Microsoft.AspNetCore.Mvc.FunctionalTests/RazorPagesTest.cs

@@ -1,6 +1,8 @@
 // Copyright (c) .NET Foundation. All rights reserved.
 // Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
 
+using System;
+using System.Linq;
 using System.Net;
 using System.Net.Http;
 using System.Threading.Tasks;
@@ -80,5 +82,66 @@ namespace Microsoft.AspNetCore.Mvc.FunctionalTests
             var content = await response.Content.ReadAsStringAsync();
             Assert.Equal("Hello, pagemodel!", content.Trim());
         }
+
+        [Fact]
+        public async Task TempData_SetTempDataInPage_CanReadValue()
+        {
+            // Arrange 1
+            var url = "http://localhost/TempData/SetTempDataOnPageAndRedirect?message=Hi1";
+            var request = new HttpRequestMessage(HttpMethod.Get, url);
+            
+            // Act 1
+            var response = await Client.SendAsync(request);
+            
+            // Assert 1
+            Assert.Equal(HttpStatusCode.Redirect, response.StatusCode);
+
+            // Arrange 2
+            request = new HttpRequestMessage(HttpMethod.Get, response.Headers.Location);
+            request.Headers.Add("Cookie", GetCookie(response));
+
+            // Act2
+            response = await Client.SendAsync(request);
+
+            var content = await response.Content.ReadAsStringAsync();
+            Assert.Equal("Hi1", content.Trim());
+        }
+
+        [Fact]
+        public async Task TempData_SetTempDataInPageModel_CanReadValue()
+        {
+            // Arrange 1
+            var url = "http://localhost/TempData/SetTempDataOnPageModelAndRedirect?message=Hi2";
+            var request = new HttpRequestMessage(HttpMethod.Get, url);
+
+            // Act 1
+            var response = await Client.SendAsync(request);
+
+            // Assert 1
+            Assert.Equal(HttpStatusCode.Redirect, response.StatusCode);
+
+            // Arrange 2
+            request = new HttpRequestMessage(HttpMethod.Get, response.Headers.Location);
+            request.Headers.Add("Cookie", GetCookie(response));
+
+            // Act2
+            response = await Client.SendAsync(request);
+
+            var content = await response.Content.ReadAsStringAsync();
+            Assert.Equal("Hi2", content.Trim());
+        }
+
+        private static string GetCookie(HttpResponseMessage response)
+        {
+            var setCookie = response.Headers.GetValues("Set-Cookie").ToArray();
+            return setCookie[0].Split(';').First();
+        }
+
+        public class CookieMetadata
+        {
+            public string Key { get; set; }
+
+            public string Value { get; set; }
+        }
     }
 }

test/WebSites/RazorPagesWebSite/Startup.cs

@@ -10,7 +10,7 @@ namespace RazorPagesWebSite
     {
         public void ConfigureServices(IServiceCollection services)
         {
-            services.AddMvc();
+            services.AddMvc().AddCookieTempDataProvider();
         }
 
         public void Configure(IApplicationBuilder app)

test/WebSites/RazorPagesWebSite/TempData/SetTempDataOnPageAndRedirect.cshtml

@@ -0,0 +1,10 @@
+@page
+
+@functions {
+
+    public IActionResult OnGet(string message)
+    {
+        TempData["Message"] = message;
+        return Redirect("~/TempData/ShowMessage");
+    }
+}

test/WebSites/RazorPagesWebSite/TempData/SetTempDataOnPageModelAndRedirect.cs

@@ -0,0 +1,17 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.AspNetCore.Mvc.RazorPages;
+
+namespace RazorPagesWebSite
+{
+    public class SetTempDataOnPageModelAndRedirect : PageModel
+    {
+        public IActionResult OnGet(string message)
+        {
+            TempData["Message"] = message;
+            return Redirect("~/TempData/ShowMessage");
+        }
+    }
+}

test/WebSites/RazorPagesWebSite/TempData/SetTempDataOnPageModelAndRedirect.cshtml

@@ -0,0 +1,2 @@
+@page
+@model RazorPagesWebSite.SetTempDataOnPageModelAndRedirect

test/WebSites/RazorPagesWebSite/TempData/ShowMessage.cshtml

@@ -0,0 +1,3 @@
+@page
+
+@(TempData["Message"])