WSUniversalLib/Calculation.cs

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

namespace WSUniversalLib
{
    public class Calculation
    {
        public static int GetQuantityForProduct(int productType, int materialType, int count, float width, float length)
        {
            float materialCount = 0f;

            if (count < 0)
            {
                throw new ArgumentException("Количество < 0");
            }
            if (width < 0)
            {
                throw new ArgumentException("Ширина < 0");
            }
            if (width == null)
            {
                throw new ArgumentNullException("ширина = NULL");
            }
            if (length < 0)
            {
                throw new ArgumentException("Длинна < 0");
            }
            if (length == null)
            {
                throw new ArgumentNullException("длинна = NULL");
            }
            switch (productType)
            {
                case 1:
                    materialCount = width * length * count * 1.1f;
                    break;
                case 2:
                    materialCount = width * length * count * 2.5f;
                    break;
                case 3:
                    materialCount = width * length * count * 8.43f;
                    break;
                default:
                    return -1;
            }
            switch (materialType)
            {
                case 1:
                    materialCount *= 1.003f;
                    break;
                case 2:
                    materialCount *= 1.0012f;
                    break;
                default:
                    return -1;
            }
            return (int)Math.Ceiling((decimal)materialCount);
        }
    }
}