Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System/compmod/system/diagnostics/BooleanSwitch.cs

@@ -0,0 +1,56 @@
+//------------------------------------------------------------------------------
+// <copyright file="BooleanSwitch.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+/*
+ */
+
+namespace System.Diagnostics {
+    using System.Diagnostics;
+    using System;
+    using System.Security;
+    using System.Security.Permissions;
+
+    /// <devdoc>
+    ///    <para>Provides a simple on/off switch that can be used to control debugging and tracing
+    ///       output.</para>
+    /// </devdoc>
+    [SwitchLevel(typeof(bool))]
+    public class BooleanSwitch : Switch {
+        /// <devdoc>
+        /// <para>Initializes a new instance of the <see cref='System.Diagnostics.BooleanSwitch'/>
+        /// class.</para>
+        /// </devdoc>
+        public BooleanSwitch(string displayName, string description)
+            : base(displayName, description) {
+        }
+
+        public BooleanSwitch(string displayName, string description, string defaultSwitchValue) 
+            : base(displayName, description, defaultSwitchValue) { }
+
+        /// <devdoc>
+        ///    <para>Specifies whether the switch is enabled
+        ///       (<see langword='true'/>) or disabled (<see langword='false'/>).</para>
+        /// </devdoc>
+        public bool Enabled {
+            get {
+                return (SwitchSetting == 0) ? false : true;
+            }
+            [SecurityPermission(SecurityAction.LinkDemand, Flags=SecurityPermissionFlag.UnmanagedCode)]
+            set {
+                SwitchSetting = value ? 1 : 0;
+            }
+        }
+
+        protected override void OnValueChanged() {
+            bool b;
+            if (Boolean.TryParse(Value, out b))
+                SwitchSetting = ( b ? 1 : 0);
+            else
+                base.OnValueChanged();
+        }
+    }
+}
+