WPF中通过附加属性实现任意控件拖动调整大小

public class ResizeBehavior
    {
        // 附加属性用于标识控件是否可调整大小
        public static readonly DependencyProperty IsResizableProperty =
            DependencyProperty.RegisterAttached("IsResizable", typeof(bool), typeof(ResizeBehavior), new PropertyMetadata(false, OnIsResizableChanged));

        public static bool GetIsResizable(DependencyObject obj)
        {
            return (bool)obj.GetValue(IsResizableProperty);
        }

        public static void SetIsResizable(DependencyObject obj, bool value)
        {
            obj.SetValue(IsResizableProperty, value);
        }

        // 当 IsResizable 附加属性发生改变时触发的回调方法
        private static void OnIsResizableChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            if (d is FrameworkElement element)
            {
                if ((bool)e.NewValue)
                {
                    element.MouseLeftButtonDown += Element_MouseLeftButtonDown;
                    element.MouseMove += Element_MouseMove;
                    element.MouseLeftButtonUp += Element_MouseLeftButtonUp;
                }
                else
                {
                    element.MouseLeftButtonDown -= Element_MouseLeftButtonDown;
                    element.MouseMove -= Element_MouseMove;
                    element.MouseLeftButtonUp -= Element_MouseLeftButtonUp;
                }
            }
        }

        private static bool isResizing = false;
        private static Point originalMousePos;
        private static double originalWidth;
        private static FrameworkElement resizingElement = null!;

        // 鼠标左键按下时触发的事件处理程序
        private static void Element_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            isResizing = true;
            originalMousePos = e.GetPosition(null);
            originalWidth = ((FrameworkElement)sender).ActualWidth;
            resizingElement = (FrameworkElement)sender;

            // 添加对鼠标左键按下事件的处理
            if (resizingElement != null)
            {
                resizingElement.CaptureMouse(); // 捕获鼠标
            }
        }

        // 鼠标移动时触发的事件处理程序
        private static void Element_MouseMove(object sender, MouseEventArgs e)
        {
            if (isResizing && resizingElement != null)
            {
                Point currentMousePos = e.GetPosition(null);
                double delta = currentMousePos.X - originalMousePos.X;
                double newWidth = originalWidth + delta;

                if (newWidth > 0)
                {
                    resizingElement.Width = newWidth;
                }
            }
        }

        // 鼠标左键释放时触发的事件处理程序
        private static void Element_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            if (isResizing && resizingElement != null)
            {
                isResizing = false;
                resizingElement.ReleaseMouseCapture(); // 释放鼠标捕获
                resizingElement = null!;
            }
        }
    }

　　

<Border service:ResizeBehavior.IsResizable="True" BorderThickness="2" BorderBrush="Gray" Cursor="SizeWE"></Border>