c# - XAML では、helpers:EnumHelper.Enum 属性は何を意味しますか?

Question

次のコード スニペットでは:

<ItemsControl helpers:EnumHelper.Enum="order:TShirtSizeEnum" ... >
...
</ItemsControl>

helpers:EnumHelper.Enum 属性とは何ですか?

次はEnumHelperクラスの実装です

public class EnumHelper : DependencyObject
{
    public static Type GetEnum(DependencyObject obj)
    {
        return (Type)obj.GetValue(EnumProperty);
    }

    public static void SetEnum(DependencyObject obj, string value)
    {
        obj.SetValue(EnumProperty, value);
    }

    // Using a DependencyProperty as the backing store for Enum.  This enables animation, styling, binding, etc...
    public static readonly DependencyProperty EnumProperty =
        DependencyProperty.RegisterAttached("Enum", typeof(Type), typeof(EnumHelper), new PropertyMetadata(null, OnEnumChanged));

    private static void OnEnumChanged(DependencyObject sender, DependencyPropertyChangedEventArgs e)
    {
        var control = sender as ItemsControl;

        if (control != null)
        {
            if (e.NewValue != null && e.NewValue as Type != null)
            {
                var _enum = Enum.GetValues(e.NewValue as Type);
                control.ItemsSource = _enum;
            }
        }
    }
}