add gesture text.

samples/ControlCatalog/Pages/TextBoxPage.xaml

@@ -3,9 +3,9 @@
   <StackPanel Orientation="Vertical" Spacing="4">
     <StackPanel.Resources>
       <ContextMenu x:Key="DefaultTextBoxContextMenu">
-        <MenuItem Header="Cut" Command="{Binding $parent[TextBox].Cut}" IsEnabled="{Binding $parent[TextBox].CanCut}"/>
-        <MenuItem Header="Copy" Command="{Binding $parent[TextBox].Copy}" IsEnabled="{Binding $parent[TextBox].CanCopy}"/>
-        <MenuItem Header="Paste" Command="{Binding $parent[TextBox].Paste}" IsEnabled="{Binding $parent[TextBox].CanPaste}"/>
+        <MenuItem Header="Cut" Command="{Binding $parent[TextBox].Cut}" IsEnabled="{Binding $parent[TextBox].CanCut}" InputGesture="{x:Static TextBox.CutGesture}" />
+        <MenuItem Header="Copy" Command="{Binding $parent[TextBox].Copy}" IsEnabled="{Binding $parent[TextBox].CanCopy}" InputGesture="{x:Static TextBox.CopyGesture}"/>
+        <MenuItem Header="Paste" Command="{Binding $parent[TextBox].Paste}" IsEnabled="{Binding $parent[TextBox].CanPaste}" InputGesture="{x:Static TextBox.PasteGesture}"/>
       </ContextMenu>
     </StackPanel.Resources>
     <StackPanel.Styles>

src/Avalonia.Controls/TextBox.cs

@@ -19,6 +19,15 @@ namespace Avalonia.Controls
 {
     public class TextBox : TemplatedControl, UndoRedoHelper<TextBox.UndoRedoState>.IUndoRedoHost
     {
+        public static KeyGesture CutGesture { get; } =
+            AvaloniaLocator.Current.GetService<PlatformHotkeyConfiguration>()?.Cut.FirstOrDefault();
+
+        public static KeyGesture CopyGesture { get; } = AvaloniaLocator.Current
+            .GetService<PlatformHotkeyConfiguration>()?.Copy.FirstOrDefault();
+
+        public static KeyGesture PasteGesture { get; } = AvaloniaLocator.Current
+            .GetService<PlatformHotkeyConfiguration>()?.Paste.FirstOrDefault();
+        
         public static readonly StyledProperty<bool> AcceptsReturnProperty =
             AvaloniaProperty.Register<TextBox, bool>(nameof(AcceptsReturn));