Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/UI/WebControls/AdPostCacheSubstitution.cs

@@ -0,0 +1,55 @@
+//------------------------------------------------------------------------------
+// <copyright file="AdPostCacheSubstitution.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+/*
+ * The class is used internally to handle post-cache substitution mechanism in
+ * AdRotator.
+ *
+ * Copyright (c) 2002 Microsoft Corporation
+ */
+namespace System.Web.UI.WebControls {
+    using System.Globalization;
+    using System.IO;
+    using System.Web.Util;
+
+    internal class AdPostCacheSubstitution {
+        private AdRotator _adRotatorHelper;
+
+        private AdPostCacheSubstitution() {}
+
+        internal AdPostCacheSubstitution(AdRotator adRotator) {
+            _adRotatorHelper = new AdRotator();
+            _adRotatorHelper.CopyFrom(adRotator);
+            _adRotatorHelper.IsPostCacheAdHelper = true;
+            _adRotatorHelper.Page = new Page();
+        }
+
+        internal void RegisterPostCacheCallBack(HttpContext context,
+                                                Page page,
+                                                HtmlTextWriter writer) {
+            // Assumption: called from AdRotator's Render phase
+
+            HttpResponseSubstitutionCallback callback = new HttpResponseSubstitutionCallback(Render);
+            context.Response.WriteSubstitution(callback);
+        }
+
+        internal string Render(HttpContext context) {
+            // 
+
+
+            Debug.Assert(_adRotatorHelper != null && _adRotatorHelper.Page != null);
+
+            // In PostCache Substitution, we use a string writer to return the markup.
+            StringWriter stringWriter = new StringWriter(CultureInfo.CurrentCulture);
+            HtmlTextWriter htmlWriter = _adRotatorHelper.Page.CreateHtmlTextWriter(stringWriter);
+            Debug.Assert(htmlWriter != null);
+            _adRotatorHelper.RenderControl(htmlWriter);
+
+            // Dump the content out as needed for post-cache substitution.
+            return stringWriter.ToString();
+        }
+    }
+}