Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/UI/ThemeableAttribute.cs

@@ -0,0 +1,108 @@
+//------------------------------------------------------------------------------
+// <copyright file="ThemeableAttribute.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+//------------------------------------------------------------------------------
+
+/*
+ */
+namespace System.Web.UI {
+
+    using System;
+    using System.Collections;
+    using System.ComponentModel;
+
+    /// <devdoc>
+    /// <para></para>
+    /// </devdoc>
+    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Class)]
+    public sealed class ThemeableAttribute : Attribute {
+
+        /// <internalonly/>
+        /// <devdoc>
+        /// <para></para>
+        /// </devdoc>
+        public static readonly ThemeableAttribute Yes = new ThemeableAttribute(true);
+
+        /// <internalonly/>
+        /// <devdoc>
+        /// <para></para>
+        /// </devdoc>
+        public static readonly ThemeableAttribute No = new ThemeableAttribute(false);
+
+        /// <internalonly/>
+        /// <devdoc>
+        /// <para></para>
+        /// </devdoc>
+        public static readonly ThemeableAttribute Default = Yes;
+
+        private bool _themeable = false;
+        private static Hashtable _themeableTypes;        
+
+        static ThemeableAttribute() {
+            // Create a synchronized wrapper
+            _themeableTypes = Hashtable.Synchronized(new Hashtable());
+        } 
+
+        /// <devdoc>
+        /// </devdoc>
+        public ThemeableAttribute(bool themeable) {
+            _themeable = themeable;
+        }
+
+        /// <devdoc>
+        ///    <para> Indicates if the property is themeable.</para>
+        /// </devdoc>
+        public bool Themeable {
+            get {
+                return _themeable;
+            }
+        }
+
+        /// <internalonly/>
+        public override bool Equals(object obj) {
+            if (obj == this) {
+                return true;
+            }
+
+            ThemeableAttribute other = obj as ThemeableAttribute;
+            return (other != null) && (other.Themeable == _themeable);
+        }
+
+        /// <internalonly/>
+        public override int GetHashCode() {
+            return _themeable.GetHashCode();
+        }
+
+        /// <internalonly/>
+        public override bool IsDefaultAttribute() {
+            return this.Equals(Default);
+        }
+
+        public static bool IsObjectThemeable(Object instance) {
+            if (instance == null)
+                throw new ArgumentNullException("instance");
+
+            return IsTypeThemeable(instance.GetType());
+        }
+
+        public static bool IsTypeThemeable(Type type) {
+            if (type == null)
+                throw new ArgumentNullException("type");
+
+            object result = _themeableTypes[type];
+            if (result != null) {
+                return (bool)result;
+            }
+
+            //System.ComponentModel.AttributeCollection attrs = TypeDescriptor.GetAttributes(type);
+            //ThemeableAttribute attr = (ThemeableAttribute)attrs[typeof(ThemeableAttribute)];
+            ThemeableAttribute attr = Attribute.GetCustomAttribute(type, typeof(ThemeableAttribute)) as ThemeableAttribute;
+            result = (attr != null) && attr.Themeable;
+            _themeableTypes[type] = result;
+
+            return (bool)result;
+        }
+    }
+}
+