wpftoolkit/ExtendedWPFToolkitSolution/Src/WPFToolkit.Extended/PropertyGrid/Implementation/Attributes/PropertyOrderAttribute.cs

using System;

namespace Microsoft.Windows.Controls.PropertyGrid.Attributes
{
    [AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
    public class PropertyOrderAttribute : Attribute
    {
        public int Order { get; set; }
        
        public PropertyOrderAttribute(int order)
        {
            Order = order;
        }
    }
}