Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System.Web/UI/WebParts/ZoneButton.cs

@@ -0,0 +1,52 @@
+//------------------------------------------------------------------------------
+// <copyright file="ZoneButton.cs" company="Microsoft">
+//     Copyright (c) Microsoft Corporation.  All rights reserved.
+// </copyright>
+//------------------------------------------------------------------------------
+
+namespace System.Web.UI.WebControls.WebParts {
+
+    using System;
+    using System.ComponentModel;
+    using System.Web.UI.WebControls;
+
+    [SupportsEventValidation]
+    internal sealed class ZoneButton : Button {
+
+        private WebZone _owner;
+        private string _eventArgument;
+
+        public ZoneButton(WebZone owner, string eventArgument) {
+            if (owner == null) {
+                throw new ArgumentNullException("owner");
+            }
+            _owner = owner;
+            _eventArgument = eventArgument;
+        }
+
+        [
+        DefaultValue(false),
+        ]
+        public override bool UseSubmitBehavior {
+            get {
+                return false;
+            }
+            set {
+                // This is an internal sealed class so we know the setter is never called.
+                throw new InvalidOperationException();
+            }
+        }
+
+        protected override PostBackOptions GetPostBackOptions() {
+            // _owner.Page may be null in the designer
+            if (!String.IsNullOrEmpty(_eventArgument) && _owner.Page != null) {
+                PostBackOptions options = new PostBackOptions(_owner, _eventArgument);
+                options.ClientSubmit = true;
+
+                return options;
+            }
+
+            return base.GetPostBackOptions();
+        }
+    }
+}