narsil/Tanshu.Accounts.Contracts/Data Contracts/InventoryBO.cs

using System;
using System.Runtime.Serialization;

namespace Tanshu.Accounts.Contracts
{

    public class InventoryBO
    {
        public Guid InventoryID { get; set; }
        public Guid VoucherID { get; set; }
        public Guid ProductID { get; set; }
        public string ProductName { get; set; }
        private decimal quantity;
        public decimal Quantity
        {
            get { return quantity; }
            set
            {
                quantity = value;
                amount = null;
            }
        }

        private decimal rate;
        public decimal Rate
        {
            get { return rate; }
            set
            {
                rate = value;
                amount = null;
            }
        }

        decimal vat;
        public decimal Vat
        {
            get { return vat; }
            set
            {
                vat = value;
                amount = null;
            }
        }

        decimal serviceTax;
        public decimal ServiceTax
        {
            get { return serviceTax; }
            set
            {
                serviceTax = value;
                amount = null;
            }
        }

        decimal discount;
        public decimal Discount
        {
            get { return discount; }
            set
            {
                discount = value;
                amount = null;
            }
        }

        decimal? amount;
        public decimal Amount
        {
            get
            {
                if (!amount.HasValue)
                    CalculateAmount();
                return amount.Value;
            }
        }
        private void CalculateAmount()
        {
            amount = quantity * rate * (1 + vat + serviceTax) * (1 - discount);
        }
    }
}