shoppingcart.aspx.vb

编程之道VB.NETt程序设计入门-589M.zip

Imports Nozama.BusinessLogic
Imports Nozama.DataAccess
Imports Nozama.General

Public Class ShoppingCart
    Inherits System.Web.UI.Page
    Protected WithEvents CheckOutHyperLink As System.Web.UI.WebControls.HyperLink
    Protected WithEvents grdOrderDetail As System.Web.UI.WebControls.DataGrid
    Protected WithEvents btnUpdate As System.Web.UI.WebControls.Button
    Protected WithEvents ShoppingCartPanel As System.Web.UI.WebControls.Panel

#Region " Web 窗体设计器生成的代码 "

    '该调用是 Web 窗体设计器所必需的。
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()

    End Sub

    Private Sub Page_Init(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Init
        'CODEGEN: 此方法调用是 Web 窗体设计器所必需的
        '不要使用代码编辑器修改它。
        InitializeComponent()
    End Sub

#End Region

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        '在此处放置初始化页的用户代码
        If Not Me.IsPostBack Then
            Dim orderDetail As DataTable
            orderDetail = GetShoppingCart().OrderDetail()

            grdOrderDetail.DataSource = orderDetail
            grdOrderDetail.DataBind()

            Dim cartHasItems As Boolean = Not GetShoppingCart().IsEmpty
            ShoppingCartPanel.Visible = cartHasItems
            grdOrderDetail.Visible = cartHasItems
            CheckOutHyperLink.Visible = cartHasItems
        End If
    End Sub

    Private Function GetShoppingCart() As Cart
        Dim cart As Cart = CType(Session().Item(Settings.ShoppingCart), Cart)

        If cart Is Nothing Then
            cart = New Cart()
            Session().Item(Settings.ShoppingCart) = cart
        End If
        Return cart

    End Function

    Private Sub btnUpdate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnUpdate.Click
        Dim cartHasItems As Boolean
        Dim i As Integer
        Dim quantity As Integer
        Dim item As DataGridItem
        Dim quantityTextBox As Web.UI.WebControls.TextBox
        Dim row As DataRow

        With GetShoppingCart()
            If Not .IsEmpty Then

                For i = 0 To grdOrderDetail.Items.Count - 1
                    item = grdOrderDetail.Items(i)
                    quantityTextBox = CType(item.FindControl("txtQuantity"), TextBox)
                    quantity = CInt(quantityTextBox.Text)
                    .OrderDetail.Rows(i).Item(OrderData.QUANTITY) = quantity
                Next i

                .UpdataCart()

                cartHasItems = Not .IsEmpty
                If cartHasItems Then
                    grdOrderDetail.DataSource = CType(.OrderDetail.DefaultView, System.Collections.ICollection)
                    grdOrderDetail.DataBind()
                End If
            End If
        End With

        ShoppingCartPanel.Visible = cartHasItems
        grdOrderDetail.Visible = cartHasItems
        CheckOutHyperLink.Visible = cartHasItems
    End Sub
End Class