ProductTest/WpfAppProduct/ClassProduct.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace WpfAppProduct
{
    public partial class Product
    {
        public string Desc
        {
            get
            {
                return "Описание: " + ProductDescription;
            }
        }
        public string Price
        {
            get
            {
                return "Стоимость: " + String.Format("{0:N2}", ProductCost);
            }
        }
        //public string Discount
        //{
        //    get
        //    {
        //        int disc = (int)ProductDiscount;
        //        double NewCost = ;
        //        return NewCost;
        //    }
        //}
    }
}