Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/ModelBinding/SessionAttribute.cs

@@ -0,0 +1,49 @@
+namespace System.Web.ModelBinding {
+    using System;
+    using System.Collections.Generic;
+    using System.Globalization;
+
+    [AttributeUsage(AttributeTargets.Parameter, Inherited = false, AllowMultiple = false)]
+    public sealed class SessionAttribute : ValueProviderSourceAttribute {
+
+        public string Name {
+            get;
+            private set;
+        }
+
+        public SessionAttribute()
+            : this(null) {
+        }
+
+        public SessionAttribute(string name) {
+            Name = name;
+        }
+
+        public override IValueProvider GetValueProvider(ModelBindingExecutionContext modelBindingExecutionContext) {
+            if (modelBindingExecutionContext == null) {
+                throw new ArgumentNullException("modelBindingExecutionContext");
+            }
+
+            HttpSessionStateBase session = modelBindingExecutionContext.HttpContext.Session;
+            if (session == null) {
+                // session is disabled
+                return null;
+            }
+
+            Dictionary<string, object> backingStore = new Dictionary<string, object>(StringComparer.OrdinalIgnoreCase);
+            foreach (string key in session) {
+                if (key != null) {
+                    backingStore[key] = session[key]; // copy to backing store
+                }
+            }
+
+            // use the invariant culture since Session contains serialized objects
+            return new DictionaryValueProvider<object>(backingStore, CultureInfo.InvariantCulture);
+        }
+
+        public override string GetModelName() {
+            return Name;
+        }
+
+    }
+}