Neuerstellung

- Quelle: https://github.com/oxyplot/oxyplot

Source/Examples/WPF/WpfExamples/DelegateCommand.cs

@@ -0,0 +1,104 @@
+// --------------------------------------------------------------------------------------------------------------------
+// <copyright file="DelegateCommand.cs" company="OxyPlot">
+//   Copyright (c) 2014 OxyPlot contributors
+// </copyright>
+// <summary>
+//   Represents a delegate command.
+// </summary>
+// --------------------------------------------------------------------------------------------------------------------
+
+namespace WpfExamples
+{
+    using System;
+    using System.Windows.Input;
+
+    /// <summary>
+    /// Represents a delegate command.
+    /// </summary>
+    public class DelegateCommand : ICommand
+    {
+        /// <summary>
+        /// The can execute.
+        /// </summary>
+        private readonly Func<bool> canExecute;
+
+        /// <summary>
+        /// The execute.
+        /// </summary>
+        private readonly Action execute;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="DelegateCommand" /> class.
+        /// </summary>
+        /// <param name="execute">The execute.</param>
+        public DelegateCommand(Action execute)
+            : this(execute, null)
+        {
+        }
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="DelegateCommand" /> class.
+        /// </summary>
+        /// <param name="execute">The execute.</param>
+        /// <param name="canExecute">The can execute.</param>
+        public DelegateCommand(Action execute, Func<bool> canExecute)
+        {
+            if (execute == null)
+            {
+                throw new ArgumentNullException("execute");
+            }
+
+            this.execute = execute;
+            this.canExecute = canExecute;
+        }
+
+        /// <summary>
+        /// Occurs when changes occur that affect whether or not the command should execute.
+        /// </summary>
+        public event EventHandler CanExecuteChanged
+        {
+            add
+            {
+                if (this.canExecute != null)
+                {
+                    CommandManager.RequerySuggested += value;
+                }
+            }
+
+            remove
+            {
+                if (this.canExecute != null)
+                {
+                    CommandManager.RequerySuggested -= value;
+                }
+            }
+        }
+
+        /// <summary>
+        /// Defines the method that determines whether the command can execute in its current state.
+        /// </summary>
+        /// <param name="parameter">Data used by the command. If the command does not require data to be passed, this object can be set to <c>null</c>.</param>
+        /// <returns><c>true</c> if this command can be executed; otherwise, <c>false</c>.</returns>
+        public bool CanExecute(object parameter)
+        {
+            return this.canExecute == null ? true : this.canExecute();
+        }
+
+        /// <summary>
+        /// Defines the method to be called when the command is invoked.
+        /// </summary>
+        /// <param name="parameter">Data used by the command. If the command does not require data to be passed, this object can be set to <c>null</c>.</param>
+        public void Execute(object parameter)
+        {
+            this.execute();
+        }
+
+        /// <summary>
+        /// Raises the can execute changed.
+        /// </summary>
+        public void RaiseCanExecuteChanged()
+        {
+            CommandManager.InvalidateRequerySuggested();
+        }
+    }
+}