C# wpf 实现自定义撤销重做功能

新建wpf项目，新建Undoable.cs（操作记录），main.xaml（页面）

using System;
using System.Collections.Generic;
namespace WpfApp1
{
    /// <summary>
    /// 撤销重做对象
    /// ceate by xin 2022.6.26
    /// 2023.9.13去除Step的定义替换为KeyValuePair简化实现
    /// </summary>
    public class Undoable
    {
        /// <summary>
        /// 撤销
        /// </summary>
        public void Undo()
        {
            if (index > -1) _steps[index--].Key();
        }
        /// <summary>
        /// 重做
        /// </summary>
        public void Redo()
        {
            if (index < _steps.Count - 1) _steps[++index].Value();
        }
        /// <summary>
        /// 清除
        /// </summary>
        public void Clear()
        {
            _steps.Clear();
            index = -1;
        }
        /// <summary>
        /// 添加操作
        /// </summary>
        /// <param name="undo">撤销</param>
        /// <param name="redo">重做</param>
        public void Add(Action undo, Action redo)
        {
            if (++index < _steps.Count) _steps.RemoveRange(index, _steps.Count - index);
            _steps.Add(new KeyValuePair<Action, Action>(undo, redo));
        }
        //记录的步骤
        List<KeyValuePair<Action, Action>> _steps = new List<KeyValuePair<Action, Action>>();
        //当前操作的下标
        int index = -1;
    }
}

<Window x:Class="WpfApp1.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:WpfApp1"
        mc:Ignorable="d"
        Title="MainWindow" Height="450" Width="800">
    <Grid>
        <StackPanel Orientation="Horizontal" VerticalAlignment="Top" >
            <Button Width="70" Height="20" Content="撤销"  Click="Button_Click"></Button>
            <Button  Width="70" Height="20" Content="重做" Click="Button_Click_1"></Button>
        </StackPanel>
        <Rectangle   Width="240" Height=" 120"  RadiusX="20" RadiusY="20" Fill="RoyalBlue"  PreviewMouseDown="Rectangle_PreviewMouseDown" 
          PreviewMouseMove="Rectangle_PreviewMouseMove" 
          PreviewMouseUp="Rectangle_PreviewMouseUp"></Rectangle>
        <Ellipse  HorizontalAlignment="Left" Width="120" Height=" 120"   Fill="GreenYellow"  PreviewMouseDown="Rectangle_PreviewMouseDown" 
          PreviewMouseMove="Rectangle_PreviewMouseMove" 
          PreviewMouseUp="Rectangle_PreviewMouseUp"></Ellipse>
    </Grid>
</Window>

using System.Windows;
using System.Windows.Input;
namespace WpfApp1
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        Undoable _undoable = new Undoable();
        //鼠标是否按下
        bool _isMouseDown = false;
        //鼠标按下的位置
        Point _mouseDownPosition;
        //鼠标按下控件的Margin
        Thickness _mouseDownMargin;
        public MainWindow()
        {
            InitializeComponent();
        }
        private void Rectangle_PreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            var c = sender as FrameworkElement;
            _isMouseDown = true;
            _mouseDownPosition = e.GetPosition(this);
            _mouseDownMargin = c.Margin;
            c.CaptureMouse();
        }

        private void Rectangle_PreviewMouseMove(object sender, MouseEventArgs e)
        {
            if (_isMouseDown)
            {
                var c = sender as FrameworkElement;
                var pos = e.GetPosition(this);
                var dp = pos - _mouseDownPosition;
                c.Margin = new Thickness(_mouseDownMargin.Left + dp.X, _mouseDownMargin.Top + dp.Y, _mouseDownMargin.Right - dp.X, _mouseDownMargin.Bottom - dp.Y);
            }
        }
        private void Rectangle_PreviewMouseUp(object sender, MouseButtonEventArgs e)
        {
            var c = sender as FrameworkElement;
            _isMouseDown = false;
            c.ReleaseMouseCapture();
            var oldMargin = _mouseDownMargin;
            var newMargin = c.Margin;
            _undoable.Add(() => {
                //撤销     
                c.Margin = oldMargin;
            }, () => {
                //重做
                c.Margin = newMargin;
            });
        }
        private void Button_Click(object sender, RoutedEventArgs e)
        {
            _undoable.Undo();
        }
        private void Button_Click_1(object sender, RoutedEventArgs e)
        {
            _undoable.Redo();
        }
    }
}