Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/Cache/SRef.cs

@@ -0,0 +1,63 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Reflection;
+using System.Security.Permissions;
+using System.Web;
+
+namespace System.Web.Caching {
+    internal class SRef {
+        private static Type s_type = Type.GetType("System.SizedReference", true, false);
+        private Object _sizedRef;
+        
+        internal SRef(Object target) {
+            _sizedRef = HttpRuntime.CreateNonPublicInstance(s_type, new object[] {target});
+        }
+        
+        internal long ApproximateSize {
+            [PermissionSet(SecurityAction.Assert, Unrestricted=true)]
+            get {
+                object o = s_type.InvokeMember("ApproximateSize",
+                                               BindingFlags.Public | BindingFlags.Instance | BindingFlags.GetProperty, 
+                                               null, // binder
+                                               _sizedRef, // target
+                                               null, // args
+                                               CultureInfo.InvariantCulture);
+                return (long) o;
+            }
+        }
+        
+        [PermissionSet(SecurityAction.Assert, Unrestricted=true)]
+        internal void Dispose() {
+            s_type.InvokeMember("Dispose",
+                                BindingFlags.Public | BindingFlags.Instance | BindingFlags.InvokeMethod, 
+                                null, // binder
+                                _sizedRef, // target
+                                null, // args
+                                CultureInfo.InvariantCulture);
+        }
+    }
+
+    internal class SRefMultiple {
+        private List<SRef> _srefs = new List<SRef>();
+
+        internal void AddSRefTarget(Object o) {
+            _srefs.Add(new SRef(o));
+        }
+
+        internal long ApproximateSize {
+            [PermissionSet(SecurityAction.Assert, Unrestricted = true)]
+            get {
+                return _srefs.Sum(s => s.ApproximateSize);
+            }
+        }
+
+        [PermissionSet(SecurityAction.Assert, Unrestricted = true)]
+        internal void Dispose() {
+            foreach (SRef s in _srefs) {
+                s.Dispose();
+            }
+        }
+    }
+}