Attached property to round corners of window on Windows 11

WindowCorner.cs

using System;
using System.Runtime.InteropServices;
using System.Windows;
using System.Windows.Interop;

internal static class WindowCorner
{
    public static bool GetIsRounded(DependencyObject obj)
    {
        return (bool)obj.GetValue(IsRoundedProperty);
    }
    public static void SetIsRounded(DependencyObject obj, bool value)
    {
        obj.SetValue(IsRoundedProperty, value);
    }
    public static readonly DependencyProperty IsRoundedProperty =
        DependencyProperty.RegisterAttached("IsRounded", typeof(bool), typeof(WindowCorner), new PropertyMetadata(false, OnIsRoundedChanged));

    private static void OnIsRoundedChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        if ((e.NewValue is not true) || (d is not Window window))
            return;

        // Apply rounded corners in desktop apps for Windows 11
        // https://learn.microsoft.com/en-us/windows/apps/desktop/modernize/ui/apply-rounded-corners
        var handle = new WindowInteropHelper(window).EnsureHandle();
        var preference = DWM_WINDOW_CORNER_PREFERENCE.DWMWCP_ROUND;

        DwmSetWindowAttribute(
            handle,
            DWMWINDOWATTRIBUTE.DWMWA_WINDOW_CORNER_PREFERENCE,
            ref preference,
            sizeof(uint));
    }

    [DllImport("dwmapi.dll")]
    private static extern void DwmSetWindowAttribute(
        IntPtr hwnd,
        DWMWINDOWATTRIBUTE attribute,
        ref DWM_WINDOW_CORNER_PREFERENCE pvAttribute,
        uint cbAttribute);

    private enum DWMWINDOWATTRIBUTE : uint
    {
        DWMWA_WINDOW_CORNER_PREFERENCE = 33
    }

    private enum DWM_WINDOW_CORNER_PREFERENCE
    {
        DWMWCP_DEFAULT = 0,
        DWMWCP_DONOTROUND = 1,
        DWMWCP_ROUND = 2,
        DWMWCP_ROUNDSMALL = 3
    }
}