Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System/compmod/system/componentmodel/design/InheritanceAttribute.cs

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+//------------------------------------------------------------------------------
+// <copyright file="InheritanceAttribute.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>                                                                
+//------------------------------------------------------------------------------
+
+/*
+ */
+namespace System.ComponentModel {
+
+    using System.Security.Permissions;
+
+    /// <devdoc>
+    ///    <para>Marks instances of objects that are inherited from their base class. This
+    ///       class cannot be inherited.</para>
+    /// </devdoc>
+    [AttributeUsage(AttributeTargets.Property | AttributeTargets.Field | AttributeTargets.Event)]
+    public sealed class InheritanceAttribute : Attribute {
+    
+        private readonly InheritanceLevel inheritanceLevel;
+
+        /// <devdoc>
+        ///    <para>
+        ///       Specifies that the component is inherited. This field is
+        ///       read-only.
+        ///    </para>
+        /// </devdoc>
+        public static readonly InheritanceAttribute Inherited = new InheritanceAttribute(InheritanceLevel.Inherited);
+
+        /// <devdoc>
+        ///    <para>
+        ///       Specifies that
+        ///       the component is inherited and is read-only. This field is
+        ///       read-only.
+        ///    </para>
+        /// </devdoc>
+        public static readonly InheritanceAttribute InheritedReadOnly = new InheritanceAttribute(InheritanceLevel.InheritedReadOnly);
+
+        /// <devdoc>
+        ///    <para>
+        ///       Specifies that the component is not inherited. This field is
+        ///       read-only.
+        ///    </para>
+        /// </devdoc>
+        public static readonly InheritanceAttribute NotInherited = new InheritanceAttribute(InheritanceLevel.NotInherited);
+
+        /// <devdoc>
+        ///    <para>
+        ///       Specifies the default value for
+        ///       the InheritanceAttribute as NotInherited.
+        ///    </para>
+        /// </devdoc>
+        public static readonly InheritanceAttribute Default = NotInherited;
+
+        /// <devdoc>
+        /// <para>Initializes a new instance of the System.ComponentModel.Design.InheritanceAttribute 
+        /// class.</para>
+        /// </devdoc>
+        public InheritanceAttribute() {
+            inheritanceLevel = Default.inheritanceLevel;
+        }
+        
+        /// <devdoc>
+        /// <para>Initializes a new instance of the System.ComponentModel.Design.InheritanceAttribute class 
+        ///    with the specified inheritance
+        ///    level.</para>
+        /// </devdoc>
+        public InheritanceAttribute(InheritanceLevel inheritanceLevel) {
+            this.inheritanceLevel = inheritanceLevel;
+        }
+        
+        /// <devdoc>
+        ///    <para>
+        ///       Gets or sets
+        ///       the current inheritance level stored in this attribute.
+        ///    </para>
+        /// </devdoc>
+        public InheritanceLevel InheritanceLevel {
+            get {
+                return inheritanceLevel;
+            }
+        }
+        
+        /// <devdoc>
+        ///    <para>
+        ///       Override to test for equality.
+        ///    </para>
+        /// </devdoc>
+        public override bool Equals(object value) {
+            if (value == this) {
+                return true;
+            }
+            
+            if (!(value is InheritanceAttribute)) {
+                return false;
+            }
+            
+            InheritanceLevel valueLevel = ((InheritanceAttribute)value).InheritanceLevel;
+            return (valueLevel == inheritanceLevel);
+        }
+
+        /// <devdoc>
+        ///    <para>
+        ///       Returns the hashcode for this object.
+        ///    </para>
+        /// </devdoc>
+        public override int GetHashCode() {
+            return base.GetHashCode();
+        }
+
+        /// <devdoc>
+        ///    <para>
+        ///       Gets whether this attribute is the default.
+        ///    </para>
+        /// </devdoc>
+        public override bool IsDefaultAttribute() {
+            return (this.Equals(Default));
+        }
+        
+        /// <devdoc>
+        ///    <para>
+        ///       Converts this attribute to a string.
+        ///    </para>
+        /// </devdoc>
+        public override string ToString() {
+            return TypeDescriptor.GetConverter(typeof(InheritanceLevel)).ConvertToString(InheritanceLevel);
+        }
+    }
+}
+