ASP.NET实现B2C显示购物车中的商品

CommonClass ccObj = new CommonClass();
    DBClass dbObj = new DBClass();
    string strSql;
    DataTable dtTable;
    Hashtable hashCar;
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            /*判断是否登录*/
            ST_check_Login();
            if (Session["ShopCart"] == null)
            {
                //如果没有购物，则给出相应信息，并隐藏按钮
                this.labMessage.Text = "您还没有购物！";
                this.labMessage.Visible = true;        //显示提示信息
                this.lnkbtnCheck.Visible = false;      //隐藏“前往服务台”按钮
                this.lnkbtnClear.Visible = false;      //隐藏“清空购物车”按钮
                this.lnkbtnContinue.Visible = false;   //隐藏“继续购物”按钮

            }
            else
            {
                hashCar = (Hashtable)Session["ShopCart"]; //获取其购物车
                if (hashCar.Count == 0)
                {
                    //如果没有购物，则给出相应信息，并隐藏按钮
                    this.labMessage.Text = "您购物车中没有商品！";
                    this.labMessage.Visible = true;        //显示提示信息
                    this.lnkbtnCheck.Visible = false;      //隐藏“前往服务台”按钮
                    this.lnkbtnClear.Visible = false;      //隐藏“清空购物车”按钮
                    this.lnkbtnContinue.Visible = false;   //隐藏“继续购物”按钮

                }
                else
                {
                    //设置购物车内容的数据源
                    dtTable = new DataTable();
                    DataColumn column1 = new DataColumn("No");        //序号列
                    DataColumn column2 = new DataColumn("BookID");    //商品ID代号
                    DataColumn column3 = new DataColumn("BookName");  //商品名称
                    DataColumn column4 = new DataColumn("Num");       //数量
                    DataColumn column5 = new DataColumn("price");     //单价
                    DataColumn column6 = new DataColumn("totalPrice");//总价
                    dtTable.Columns.Add(column1);  //添加新列           
                    dtTable.Columns.Add(column2);
                    dtTable.Columns.Add(column3);
                    dtTable.Columns.Add(column4);
                    dtTable.Columns.Add(column5);
                    dtTable.Columns.Add(column6);
                    DataRow row;
                    //对数据表中每一行进行遍历，给每一行的新列赋值
                    foreach (object key in hashCar.Keys)
                    {
                        row = dtTable.NewRow();
                        row["BookID"] = key.ToString();
                        row["Num"] = hashCar[key].ToString();
                        dtTable.Rows.Add(row);
                    }
                    //计算价格
                    DataTable dstable;
                    int i = 1;
                    float price;//商品单价
                    int count;  //商品数量
                    float totalPrice = 0; //商品总价格
                    foreach (DataRow drRow in dtTable.Rows)
                    {
                        strSql = "select BookName,HotPrice from tb_BookInfo where BookID=" + Convert.ToInt32(drRow["BookID"].ToString());
                        dstable = dbObj.GetDataSetStr(strSql, "tbGI");
                        drRow["No"] = i;//序号
                        drRow["BookName"] = dstable.Rows[0][0].ToString();//商品名称
                        drRow["price"] = (dstable.Rows[0][1].ToString());//单价
                        price = float.Parse(dstable.Rows[0][1].ToString());//单价
                        count = Int32.Parse(drRow["Num"].ToString());
                        drRow["totalPrice"] = price * count; //总价
                        totalPrice += price * count; //计算合价
                        i++;
                    }
                    this.labTotalPrice.Text = "总价：" + totalPrice.ToString();  //显示所有商品的价格
                    this.gvShopCart.DataSource = dtTable.DefaultView;   //绑定GridView控件
                    this.gvShopCart.DataKeyNames = new string[] { "BookID" };
                    this.gvShopCart.DataBind();
                }
            }
       
        }
      
    }
    public void ST_check_Login()
    {

        if ((Session["Username"] == null))
        {
            Response.Write("<script>alert('对不起！您不是会员，请先注册！');location='Default.aspx'</script>");
            Response.End();
        }
    }
    public void bind()
    {
        if (Session["ShopCart"] == null)
        {
            //如果没有购物，则给出相应信息，并隐藏按钮
            this.labMessage.Text = "您还没有购物！";
            this.labMessage.Visible = true;        //显示提示信息
            this.lnkbtnCheck.Visible = false;      //隐藏“前往服务台”按钮
            this.lnkbtnClear.Visible = false;      //隐藏“清空购物车”按钮
            this.lnkbtnContinue.Visible = false;   //隐藏“继续购物”按钮
           
        }
        else
        {
            hashCar = (Hashtable)Session["ShopCart"]; //获取其购物车
            if (hashCar.Count == 0)
            {
                //如果没有购物，则给出相应信息，并隐藏按钮
                this.labMessage.Text = "您购物车中没有商品！";
                this.labMessage.Visible = true;        //显示提示信息
                this.lnkbtnCheck.Visible = false;      //隐藏“前往服务台”按钮
                this.lnkbtnClear.Visible = false;      //隐藏“清空购物车”按钮
                this.lnkbtnContinue.Visible = false;   //隐藏“继续购物”按钮
              
            }
            else
            {
                //设置购物车内容的数据源
                dtTable = new DataTable();
                DataColumn column1 = new DataColumn("No");        //序号列
                DataColumn column2 = new DataColumn("BookID");    //商品ID代号
                DataColumn column3 = new DataColumn("BookName");  //商品名称
                DataColumn column4 = new DataColumn("Num");       //数量
                DataColumn column5 = new DataColumn("price");     //单价
                DataColumn column6 = new DataColumn("totalPrice");//总价
                dtTable.Columns.Add(column1);  //添加新列           
                dtTable.Columns.Add(column2);
                dtTable.Columns.Add(column3);
                dtTable.Columns.Add(column4);
                dtTable.Columns.Add(column5);
                dtTable.Columns.Add(column6);
                DataRow row;
                //对数据表中每一行进行遍历，给每一行的新列赋值
                foreach (object key in hashCar.Keys)
                {
                    row = dtTable.NewRow();
                    row["BookID"] = key.ToString();
                    row["Num"] = hashCar[key].ToString();
                    dtTable.Rows.Add(row);
                }
                //计算价格
                DataTable dstable;
                int i = 1;
                float price;//商品单价
                int count;  //商品数量
                float totalPrice = 0; //商品总价格
                foreach (DataRow drRow in dtTable.Rows)
                {
                    strSql = "select BookName,HotPrice from tb_BookInfo where BookID=" + Convert.ToInt32(drRow["BookID"].ToString());
                    dstable = dbObj.GetDataSetStr(strSql, "tbGI");
                    drRow["No"] = i;//序号
                    drRow["BookName"] = dstable.Rows[0][0].ToString();//商品名称
                    drRow["price"] = (dstable.Rows[0][1].ToString());//单价
                    price = float.Parse(dstable.Rows[0][1].ToString());//单价
                    count = Int32.Parse(drRow["Num"].ToString());
                    drRow["totalPrice"] = price * count; //总价
                    totalPrice += price * count; //计算合价
                    i++;
                }
                this.labTotalPrice.Text = "总价：" + totalPrice.ToString();  //显示所有商品的价格
                this.gvShopCart.DataSource = dtTable.DefaultView;   //绑定GridView控件
                this.gvShopCart.DataKeyNames=new string[] {"BookID"};
                this.gvShopCart.DataBind();
            }
        }
           
   
   
    }
    protected void lnkbtnUpdate_Click(object sender, EventArgs e)
    {
        hashCar = (Hashtable)Session["ShopCart"];  //获取其购物车
        //使用foreach语句，遍历更新购物车中的商品数量
        foreach (GridViewRow gvr in this.gvShopCart.Rows)
        {
            TextBox otb = (TextBox)gvr.FindControl("txtNum"); //找到用来输入数量的TextBox控件
            int count = Int32.Parse(otb.Text);//获得用户输入的数量值
            string BookID = gvr.Cells[1].Text;//得到该商品的ID代
            hashCar[BookID] = count;//更新hashTable表
        }
        Session["ShopCart"] = hashCar;//更新购物车
        Response.Redirect("shopCart.aspx");
    }
    protected void lnkbtnDelete_Command(object sender, CommandEventArgs e)
    {
        hashCar = (Hashtable)Session["ShopCart"];//获取其购物车
        //从Hashtable表中，将指定的商品从购物车中移除，其中，删除按钮(lnkbtnDelete)的CommandArgument参数值为商品ID代号
        hashCar.Remove(e.CommandArgument);
        Session["ShopCart"] = hashCar; //更新购物车
        Response.Redirect("shopCart.aspx");
    }
    protected void lnkbtnClear_Click(object sender, EventArgs e)
    {
        Session["ShopCart"] =null;
        Response.Redirect("shopCart.aspx");
    }
    protected void lnkbtnContinue_Click(object sender, EventArgs e)
    {
        Response.Redirect("Default.aspx");
    }
    protected void lnkbtnCheck_Click(object sender, EventArgs e)
    {
        Response.Redirect("checkOut.aspx");
    }
    protected void gvShopCart_PageIndexChanging(object sender, GridViewPageEventArgs e)
    {
        gvShopCart.PageIndex = e.NewPageIndex;
        bind();

    }
    protected void txtNum_TextChanged(object sender, EventArgs e)
    {
        hashCar = (Hashtable)Session["ShopCart"];  //获取其购物车
        foreach (GridViewRow gvr in this.gvShopCart.Rows)
        {

            TextBox otb = (TextBox)gvr.FindControl("txtNum"); //找到用来输入数量的TextBox控件
            int count = Int32.Parse(otb.Text);//获得用户输入的数量值
            string BookID = gvr.Cells[1].Text;//得到该商品的ID代
            hashCar[BookID] = count;//更新hashTable表

        }
        Session["ShopCart"] = hashCar;//更新购物车
        bind();

    }