For chapter 13 shopping cart...after i key in all the code follow as the book i get such error:


Compilation Error
Description: An error occurred during the compilation of a resource required to service this request. Please review the following specific error details and modify your source code appropriately.

Compiler Error Message: CS0234: The type or namespace name 'Commerce' does not exist in the namespace 'M2L' (are you missing an assembly reference?)

Source Error:

Line 80: }
Line 81:
Line 82: public virtual M2L.Commerce.CartItem Cart {
Line 83: get {
Line 84: return ((M2L.Commerce.CartItem)(this.GetPropertyValue("Ca rt")));


Source File: c:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Temp orary ASP.NET Files\root\6f98d0e5\9285cdca\App_Code.otcjhtkr.0.c s Line: 82


*i already define => namespace M2L.Commerce under Shopping.cs


and i also tried to download original source code from this web side i also get the same problem.

following will be my shopping.cs file:



using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data .SqlClient ;
using System.Collections .Generic ;

namespace M2L.Commerce
{
[Serializable ]
    public class CartItem
    {
        private string _productModel;
        private string _productName;
        private string _productImageUrl;
        private int _quantity;
        private double _price;
        private double _lineTotal;

        public void New()
        {
        }

        public void New(string Product_Model, string Product_Name, string Product_ImageUrl, int Quantity, double Price)
        {
            _productModel = Product_Model;
            _productName = Product_Name;
            _productImageUrl = Product_ImageUrl;
            _quantity = Quantity;
            _price = Price;
            _lineTotal = Quantity * Price;
        }

        public string ProductModel
        {
            get
            {
                return _productModel;
            }
            set
            {
                _productModel = value;
            }
        }

        public string ProductName
        {
            get
            {
                return _productName;
            }
            set
            {
                _productName = value;
            }
        }

        public string ProductImageUrl
        {
            get
            {
                return _productImageUrl;
            }
            set
            {
                _productImageUrl = value;
            }
        }

        public int Quantity
        {
            get
            {
                return _quantity;
            }
            set
            {
                _quantity = value;
            }
        }

        public double Price
        {
            get
            {
                return _price;
            }
            set
            {
                _price = value;
            }

        }

        public double LineTotal
        {
            get
            {
                return _quantity * _price;
            }
        }


        [Serializable ]
        public class ShoppingCart
        {
            private DateTime _dateCreated;
            private DateTime _lastUpdate;
            private ListBox<CartItem> _items;

            public ShoppingCart()
            {
                if (this._items == null)
                {
                    this._items = new ListBox<CartItem >();
                    this._dateCreated = DateTime .Now ;
                }
        }

            public List<CartItem> Items
            {
                get
                {
                    return _items ;
                }
                set
                {
                    _items =value;
                }
            }

            public void Insert(string Product_Model, double Price, int Quantity, string Product_Name, string Product_ImageUrl)
            {
                int ItemIndex = ItemIndexOfID(Product_Model );
                if(ItemIndex == -1)
                {
                    CartItem NewItem = new CartItem ();
                    NewItem .ProductModel = Product_Model ;
                    NewItem .Price = Price;
                    NewItem .ProductName = Product_Name ;
                    NewItem .ProductImageUrl = Product_ImageUrl ;
                 _items .Add(NewItem );
                }
                else
                {
                    _items[ItemIndex ].Quantity +=1;
                }
                _lastUpdate = DateTime .Now;
            }

            public void Update(int Row_ID, string Product_Model, double Price)
            {
                CartItem Item = _items [RowID ];
                Item .ProductModel = Product_Model ;
                Item .Quantity = Quantity;
                Item .Price = Price ;
                _lastUpdate = DateTime .Now ;
            }

            public void DeleteItem(int Row_ID)
            {
                _items .RemoveAt(Row_ID );
                _lastUpdate = DateTime .Now ;
            }

            private int ItemIndexOfID(string Product_Model)
            {
                int index = 0;
                foreach (CartItem item in _items)
                {
                    if (item.ProductModel == Product_Model)
                    {
                        return index;
                    }
                    index += 1;
                }
                return -1;
            }

            public double Total
            {
                get
                {
                    double t=0;

                    if (_items == null)
                    {
                        return 0;
                    }

                    foreach (CartItem Item in _items )

                    {
                        t += Item.LineTotal;
                    }

                    return t;
                }
            }

            }

    }
}