[网络收集]asp.net中购物车的两种存储方式Session和Cookie的应用实例

1.这是用Cookie存储的购物车的几种常用的操作：

/// <summary>
/// 使用Cookie的购物车
/// </summary>
public class CookieCar {
public const string COOKIE_CAR = "Car"; //cookie中的购物车

/// <summary>
/// 无参数的构造方法
/// </summary>
public CookieCar() {
}

/// <summary>
/// 添加商品到购物车
/// </summary>
/// <param name="id"></param>
/// <param name="quantity"></param>
public void AddProductToCar(string id, string quantity) {
string product = id + "," + quantity;
//购物车中没有该商品
if (!VerDictCarIsExit(id)) {
string oldCar = GetCarInfo();
string newCar = null;
if (oldCar != "") {
oldCar += "|";
}
newCar += oldCar + product;
AddCar(newCar);
}
else {
int count = int.Parse(GetProductInfo(id).Split(',')[1].ToString());
UpdateQuantity(id, count + 1);
}
}

/// <summary>
/// 添加商品的数量
/// </summary>
/// <param name="id"></param>
public void UpdateQuantity(string id, int quantity) {
//得到购物车
string products = GetCarInfo();
products = "|" + products + "|";
string oldProduct = "|" + GetProductInfo(id) + "|";
if (products != "") {
string oldCar = GetCarInfo();
string newProduct = "|" + id + "," + quantity + "|";
products = products.Replace(oldProduct, newProduct);
products = products.TrimStart('|').TrimEnd('|');
AddCar(products);
}
}

/// <summary>
/// 得到购物车
/// </summary>
/// <returns></returns>
public string GetCarInfo() {
if (HttpContext.Current.Request.Cookies[COOKIE_CAR] != null) {
return HttpContext.Current.Request.Cookies[COOKIE_CAR].Value.ToString();
}
return "";
}

/// <summary>
/// 根据ID得到购物车中一种商品的信息
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
private string GetProductInfo(string id) {
string productInfo = null;
//得到购物车中的所有商品
string products = GetCarInfo();
foreach (string product in products.Split('|')) {
if (id == product.Split(',')[0]) {
productInfo = product;
break;
}
}
return productInfo;
}

/// <summary>
/// 加入购物车
/// </summary>
private void AddCar(string product) {
HttpCookie car = new HttpCookie(COOKIE_CAR, product);
car.Expires = DateTime.Now.AddDays(7);
HttpContext.Current.Response.Cookies.Remove(COOKIE_CAR);
HttpContext.Current.Response.Cookies.Add(car);
}

/// <summary>
/// 判断商品是否存在
/// </summary>
/// <param name="id"></param>
/// <returns></returns>
private bool VerDictCarIsExit(string id) {
//存在的标志: true 有， false 没有
bool flag = false;
//得到购物车中的所有商品
string products = GetCarInfo();
foreach (string product in products.Split('|')) {
if (id == product.Split(',')[0]) {
flag = true;
break;
}
}
return flag;
}

/// <summary>
/// 通过商品编号删除订单
/// </summary>
/// <param name="id"></param>
public void DeleteProduct(string id) {
string oldProduct = GetProductInfo(id);
oldProduct = "|"+oldProduct+"|";
string products = GetCarInfo();
if(products != "") {
products = "|"+products+"|";
products = products.Replace(oldProduct, "|");
products = products.TrimStart('|').TrimEnd('|');
AddCar(products);
}
}

/// <summary>
/// 晴空购物车
/// </summary>
public void ClearCar() {
AddCar("");
}

/// <summary>
/// 确认订单
/// </summary>
public void ConfirmOrder(System.Web.UI.Page page, double orderTotalPrice, User user) {
//得到订单信息
string products = GetCarInfo();
if (products != "") {
string message =null;
if (ProductManager.OrderConfirm(products, orderTotalPrice, user, out message)) {
ClearCar();
}
Javascript.Alert(page, message, "Default.aspx");
}
else {
Javascript.Alert(page, "订单为空，请选择商品！", "ProductList.aspx");
}
}
}

/// <summary>
/// 得到购物车数据
/// </summary>
public DataSet GetCarData(GridView gv) {
string carInfo = new CookieCar().GetCarInfo();
if (carInfo != "") {
string sql = "";
foreach (string product in carInfo.Split('|')) {
int id = int.Parse(product.Split(',')[0].ToString());
int buyCount = int.Parse(product.Split(',')[1].ToString());
if (sql != "") {
sql += " union ";
}
sql += "select *, " + buyCount + " as buyCount, Price*" + buyCount + " as totalPrice from Products where Id = " + id;
}
TotalPrice(gv); //计算总价
return ProductManager.GetCarBySql(sql);
}
else {
Javascript.GoError("购物车为空，请选择商品！");
}
return null;
}

/// <summary>
/// 计算总价
/// </summary>
public double TotalPrice(GridView gv) {
double totalCarPrice = 0d;
foreach (GridViewRow row in gv.Rows) {
int rowIndex = row.RowIndex;
double totalPrice = double.Parse((gv.Rows[rowIndex].FindControl("lblTotalPrice") as Label).Text.ToString());
totalCarPrice += totalPrice;
}
return totalCarPrice;
}

2.这是用Session存储的购物车：

/// <summary>
/// 使用Session的购物车
/// </summary>
public class SessionCar {
private const string SESSION_CAR = "Car";

/// <summary>
/// 无参数的购物车
/// </summary>
public SessionCar() {
}

/// <summary>
/// 添加商品到购物车
/// </summary>
public void AddCart(Product product) {
if (HttpContext.Current.Session["CurrentUser"] != null) {
if (HttpContext.Current.Session[SESSION_CAR] == null) {
BuildCart(product);
}
else {
DataTable cart = HttpContext.Current.Session[SESSION_CAR] as DataTable;
if (ExistProduct(cart, product.Id)) {
this.BuildSession(cart, product);
}
}
HttpContext.Current.Response.Redirect("Cart.aspx");
}
else {
HttpContext.Current.Response.Redirect("Login.aspx");
}
}

/// <summary>
/// 已有产品
/// </summary>
/// <param name="cart"></param>
/// <returns></returns>
public bool ExistProduct(DataTable cart, int id) {
foreach (DataRow dr in cart.Rows) {
if (dr["Id"].ToString().Equals(id.ToString())) {
dr["buyCount"] = Convert.ToInt32(dr["buyCount"]) + 1;
HttpContext.Current.Session[SESSION_CAR] = cart;
HttpContext.Current.Response.Redirect("Cart.aspx");
}
}
return true;
}

/// <summary>
/// 新建购物车
/// </summary>
public void BuildCart(Product product) {
DataTable cart = new DataTable();
DataColumn[] dc = new DataColumn[] {
new DataColumn("Id"),
new DataColumn("Name"),
new DataColumn("buyCount"),
new DataColumn("Price"),
new DataColumn("Picture"),
new DataColumn("Number"),
new DataColumn("SellNumber")
};
cart.Columns.AddRange(dc);
BuildSession(cart, product);
}

/// <summary>
/// 添加新商品
/// </summary>
/// <param name="cart"></param>
public void BuildSession(DataTable cart, Product product) {
DataRow dr = cart.NewRow();
dr[0] = product.Id;
dr[1] = product.Name;
dr[2] = "1";
dr[3] = product.Price;
dr[4] = product.Picture;
dr[5] = product.Number;
dr[6] = product.SellNumber;
cart.Rows.Add(dr);
HttpContext.Current.Session[SESSION_CAR] = cart;
}

public DataTable GetCar() {
if (HttpContext.Current.Session[SESSION_CAR] != null) {
DataTable car = HttpContext.Current.Session[SESSION_CAR] as DataTable;
return car;
}
else {
return null;
}
}

/// <summary>
/// 计算总价
/// </summary>
/// <param name="cart"></param>
public double TotalPrice(DataTable cart) {
double total = 0;
foreach (DataRow dr in cart.Rows) {
total += Convert.ToDouble(dr["Price"]) * (Convert.ToInt32(dr[2].ToString()));
}
return total;
}
}

摘自http://hi.baidu.com/devid_pitoushi/blog/item/44419339d18ae0cad4622537.html