Imported Upstream version 3.6.0

Former-commit-id: da6be194a6b1221998fc28233f2503bd61dd9d14

external/rx/Rx/NET/Source/System.Reactive.Windows.Forms/Reactive/Linq/ControlObservable.cs

@@ -0,0 +1,53 @@
+// Copyright (c) Microsoft Open Technologies, Inc. All rights reserved. See License.txt in the project root for license information.
+
+using System.Reactive.Concurrency;
+using System.Windows.Forms;
+
+namespace System.Reactive.Linq
+{
+    /// <summary>
+    /// Provides a set of static methods for subscribing to IObservables using Windows Forms controls.
+    /// </summary>
+    public static class ControlObservable
+    {
+        /// <summary>
+        /// Wraps the source sequence in order to run its subscription and unsubscription logic on the Windows Forms message loop associated with the specified control.
+        /// </summary>
+        /// <typeparam name="TSource">The type of the elements in the source sequence.</typeparam>
+        /// <param name="source">Source sequence.</param>
+        /// <param name="control">Windows Forms control whose associated message loop is used to to perform subscription and unsubscription actions on.</param>
+        /// <returns>The source sequence whose subscriptions and unsubscriptions happen on the Windows Forms message loop associated with the specified control.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="control"/> is null.</exception>
+        /// <remarks>
+        /// Only the side-effects of subscribing to the source sequence and disposing subscriptions to the source sequence are run on the specified control.
+        /// In order to invoke observer callbacks on the specified control, e.g. to render results in a control, use <see cref="ControlObservable.ObserveOn"/>.
+        /// </remarks>
+        public static IObservable<TSource> SubscribeOn<TSource>(this IObservable<TSource> source, Control control)
+        {
+            if (source == null)
+                throw new ArgumentNullException("source");
+            if (control == null)
+                throw new ArgumentNullException("control");
+
+            return Synchronization.SubscribeOn(source, new ControlScheduler(control));
+        }
+
+        /// <summary>
+        /// Wraps the source sequence in order to run its observer callbacks on the Windows Forms message loop associated with the specified control.
+        /// </summary>
+        /// <typeparam name="TSource">The type of the elements in the source sequence.</typeparam>
+        /// <param name="source">Source sequence.</param>
+        /// <param name="control">Windows Forms control whose associated message loop is used to to notify observers on.</param>
+        /// <returns>The source sequence whose observations happen on the Windows Forms message loop associated with the specified control.</returns>
+        /// <exception cref="ArgumentNullException"><paramref name="source"/> or <paramref name="control"/> is null.</exception>
+        public static IObservable<TSource> ObserveOn<TSource>(this IObservable<TSource> source, Control control)
+        {
+            if (source == null)
+                throw new ArgumentNullException("source");
+            if (control == null)
+                throw new ArgumentNullException("control");
+
+            return Synchronization.ObserveOn(source, new ControlScheduler(control));
+        }
+    }
+}