整理整理

AIStudio.Wpf.DiagramDesigner.Additionals/Commands/CommandReference.cs

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+using System;
+using System.Windows;
+using System.Windows.Input;
+
+namespace AIStudio.Wpf.DiagramDesigner.Additionals.Commands
+{
+    public class CommandReference : Freezable, ICommand
+    {
+        public CommandReference()
+        {
+            // Blank
+        }
+
+        public static readonly DependencyProperty CommandProperty = DependencyProperty.Register("Command", typeof(ICommand), typeof(CommandReference), new PropertyMetadata(new PropertyChangedCallback(OnCommandChanged)));
+
+        public ICommand Command
+        {
+            get { return (ICommand)GetValue(CommandProperty); }
+            set { SetValue(CommandProperty, value); }
+        }
+
+        #region ICommand Members
+
+        public bool CanExecute(object parameter)
+        {
+            if (Command != null)
+                return Command.CanExecute(parameter);
+            return false;
+        }
+
+        public void Execute(object parameter)
+        {
+            Command.Execute(parameter);
+        }
+
+        public event EventHandler CanExecuteChanged;
+
+        private static void OnCommandChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            CommandReference commandReference = d as CommandReference;
+            ICommand oldCommand = e.OldValue as ICommand;
+            ICommand newCommand = e.NewValue as ICommand;
+
+            if (oldCommand != null)
+            {
+                oldCommand.CanExecuteChanged -= commandReference.CanExecuteChanged;
+            }
+            if (newCommand != null)
+            {
+                newCommand.CanExecuteChanged += commandReference.CanExecuteChanged;
+            }
+        }
+
+        #endregion
+
+        #region Freezable
+
+        protected override Freezable CreateInstanceCore()
+        {
+            throw new NotImplementedException();
+        }
+
+        #endregion
+    }
+}