WPF - Canvas를 이용한 도형 이동 및 크기고

<Window x:Class="WpfApp6.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:WpfApp6"
        mc:Ignorable="d"
         Width="400" Height="400"
        MouseMove="Window_MouseMove" MouseUp="Window_MouseUp">
    <Canvas Name="canvas">
        <Rectangle Name="box" Width="50" Height="50" Fill="Red"
                   Canvas.Left="50" Canvas.Top="50"
                   MouseDown="Box_MouseDown" MouseMove="Box_MouseMove"/>
        <Rectangle Name="handle" Width="10" Height="10" Fill="Blue"
                   Canvas.Left="75" Canvas.Top="40"
                   MouseDown="Handle_MouseDown" MouseMove="Handle_MouseMove"/>
    </Canvas>
</Window>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace WpfApp6
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        private bool isDragging;
        private Point lastPosition;

        public MainWindow()
        {
            InitializeComponent();
        }

        private void Box_MouseDown(object sender, MouseButtonEventArgs e)
        {
            isDragging = true;
            lastPosition = e.GetPosition(canvas);
            box.CaptureMouse();
        }

        private void Box_MouseMove(object sender, MouseEventArgs e)
        {
            if (isDragging)
            {
                Point currentPosition = e.GetPosition(canvas);
                double deltaX = currentPosition.X - lastPosition.X;
                double deltaY = currentPosition.Y - lastPosition.Y;

                double newLeft = Canvas.GetLeft(box) + deltaX;
                double newTop = Canvas.GetTop(box) + deltaY;

                Canvas.SetLeft(box, newLeft);
                Canvas.SetTop(box, newTop);

                Canvas.SetLeft(handle, Canvas.GetLeft(handle) + deltaX);
                Canvas.SetTop(handle, Canvas.GetTop(handle) + deltaY);

                lastPosition = currentPosition;
            }
        }

        private void Handle_MouseDown(object sender, MouseButtonEventArgs e)
        {
            isDragging = true;
            lastPosition = e.GetPosition(canvas);
            handle.CaptureMouse();
        }

        private void Handle_MouseMove(object sender, MouseEventArgs e)
        {
            if (isDragging)
            {
                Point currentPosition = e.GetPosition(canvas);
                double deltaX = currentPosition.X - lastPosition.X;
                double deltaY = currentPosition.Y - lastPosition.Y;

                double newWidth = box.Width + deltaX;
                double newHeight = box.Height + deltaY;

                if (newHeight > 0)
                {
                    box.Height = newHeight;
                    Canvas.SetTop(handle, Canvas.GetTop(handle) + deltaY);
                }

                if (newWidth > 0)
                {
                    box.Width = newWidth;
                    Canvas.SetLeft(handle, Canvas.GetLeft(handle) + deltaX);
                }

                lastPosition = currentPosition;
            }
        }

        private void Window_MouseUp(object sender, MouseButtonEventArgs e)
        {
            isDragging = false;
            box.ReleaseMouseCapture();
            handle.ReleaseMouseCapture();
        }

        private void Window_MouseMove(object sender, MouseEventArgs e)
        {
            if (isDragging && e.LeftButton == MouseButtonState.Released)
            {
                isDragging = false;
                box.ReleaseMouseCapture();
                handle.ReleaseMouseCapture();
            }
        }
    }
}