Added KeyUp event.

Perspex.Input/InputElement.cs

@@ -46,6 +46,11 @@ namespace Perspex.Input
                 "KeyDown", 
                 RoutingStrategies.Tunnel | RoutingStrategies.Bubble);
 
+        public static readonly RoutedEvent<KeyEventArgs> KeyUpEvent =
+            RoutedEvent.Register<InputElement, KeyEventArgs>(
+                "KeyUp",
+                RoutingStrategies.Tunnel | RoutingStrategies.Bubble);
+
         public static readonly RoutedEvent<PointerEventArgs> PointerEnterEvent =
             RoutedEvent.Register<InputElement, PointerEventArgs>("PointerEnter", RoutingStrategies.Direct);
 
@@ -79,6 +84,7 @@ namespace Perspex.Input
             GotFocusEvent.AddClassHandler<InputElement>(x => x.OnGotFocus);
             LostFocusEvent.AddClassHandler<InputElement>(x => x.OnLostFocus);
             KeyDownEvent.AddClassHandler<InputElement>(x => x.OnKeyDown);
+            KeyDownEvent.AddClassHandler<InputElement>(x => x.OnKeyUp);
             PointerEnterEvent.AddClassHandler<InputElement>(x => x.OnPointerEnter);
             PointerLeaveEvent.AddClassHandler<InputElement>(x => x.OnPointerLeave);
             PointerMovedEvent.AddClassHandler<InputElement>(x => x.OnPointerMoved);
@@ -105,6 +111,12 @@ namespace Perspex.Input
             remove { this.RemoveHandler(KeyDownEvent, value); }
         }
 
+        public event EventHandler<KeyEventArgs> KeyUp
+        {
+            add { this.AddHandler(KeyUpEvent, value); }
+            remove { this.RemoveHandler(KeyUpEvent, value); }
+        }
+
         public event EventHandler<PointerEventArgs> PointerEnter
         {
             add { this.AddHandler(PointerEnterEvent, value); }
@@ -243,6 +255,10 @@ namespace Perspex.Input
             }
         }
 
+        protected virtual void OnKeyUp(KeyEventArgs e)
+        {
+        }
+
         protected virtual void OnPointerEnter(PointerEventArgs e)
         {
             this.IsPointerOver = true;

Perspex.Input/KeyboardDevice.cs

@@ -83,9 +83,13 @@ namespace Perspex.Input
                 switch (e.Type)
                 {
                     case RawKeyEventType.KeyDown:
+                    case RawKeyEventType.KeyUp:
+                        var routedEvent = e.Type == RawKeyEventType.KeyDown ?
+                            InputElement.KeyDownEvent : InputElement.KeyUpEvent;
+
                         KeyEventArgs ev = new KeyEventArgs
                         {
-                            RoutedEvent = InputElement.KeyDownEvent,
+                            RoutedEvent = routedEvent,
                             Device = this,
                             Key = e.Key,
                             Text = e.Text,

Windows/Perspex.Win32/WindowImpl.cs

@@ -256,6 +256,17 @@ namespace Perspex.Win32
                             WindowsKeyboardDevice.Instance.StringFromVirtualKey((uint)wParam));
                     break;
 
+                case UnmanagedMethods.WindowsMessage.WM_KEYUP:
+                case UnmanagedMethods.WindowsMessage.WM_SYSKEYUP:
+                    WindowsKeyboardDevice.Instance.UpdateKeyStates();
+                    e = new RawKeyEventArgs(
+                            WindowsKeyboardDevice.Instance,
+                            timestamp,
+                            RawKeyEventType.KeyUp,
+                            KeyInterop.KeyFromVirtualKey((int)wParam),
+                            WindowsKeyboardDevice.Instance.StringFromVirtualKey((uint)wParam));
+                    break;
+
                 case UnmanagedMethods.WindowsMessage.WM_LBUTTONDOWN:
                     e = new RawMouseEventArgs(
                         WindowsMouseDevice.Instance,