Question

所以，我有一个select查询，我从一个页面上的下拉列表中选择值，并在SELECT查询中使用它。我遇到的问题是，当我从一个页面导航到下一个页面时，cookie不会在查询中使用。如果有人能弄清楚原因，那就太棒了。

我的两个页面的代码如下：

主页

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>

<!DOCTYPE html>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

        <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>" SelectCommand="SELECT [ProductName] FROM [Products]"></asp:SqlDataSource>
        <br />
        <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="SqlDataSource1" DataTextField="ProductName" DataValueField="ProductName">
        </asp:DropDownList>
        <br />
        <br />
        <asp:LinkButton ID="LinkButton1" runat="server" PostBackUrl="~/infopage.aspx">Information Screen</asp:LinkButton>
        <br />
        <asp:LinkButton ID="LinkButton2" runat="server" PostBackUrl="~/Orders.aspx">Orders Screen</asp:LinkButton>
        <br />
        <asp:LinkButton ID="LinkButton3" runat="server" PostBackUrl="~/Items.aspx">Items Screen</asp:LinkButton>
        <br />
        <asp:LinkButton ID="LinkButton4" runat="server" PostBackUrl="~/Totals.aspx">Total Screen</asp:LinkButton>

    </div>
    </form>
</body>
</html>

第一个链接页面：

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="infopage.aspx.vb" Inherits="infopage" %>
    <!DOCTYPE html>

    <html xmlns="http://www.w3.org/1999/xhtml">
    <head runat="server">
        <title></title>
    </head>
    <body>
        <form id="form1" runat="server">
        <div>

            <asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:NorthwindConnectionString %>" SelectCommand="SELECT [ProductID], [ProductName], [SupplierID], [CategoryID], [QuantityPerUnit], [UnitPrice], [UnitsInStock], [UnitsOnOrder], [Discontinued], [ReorderLevel] FROM [Products] WHERE [ProductName] = @p1">
                <SelectParameters>
                    <asp:CookieParameter CookieName="product" Name="p1" />
                </SelectParameters>
            </asp:SqlDataSource>
            <asp:DetailsView ID="DetailsView1" runat="server" AutoGenerateRows="False" BackColor="LightGoldenrodYellow" BorderColor="Tan" BorderWidth="1px" CellPadding="2" DataKeyNames="ProductID" DataSourceID="SqlDataSource1" ForeColor="Black" GridLines="None" Height="50px" Width="125px">
                <AlternatingRowStyle BackColor="PaleGoldenrod" />
                <EditRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" />
                <Fields>
                    <asp:BoundField DataField="ProductID" HeaderText="ProductID" InsertVisible="False" ReadOnly="True" SortExpression="ProductID" />
                    <asp:BoundField DataField="ProductName" HeaderText="ProductName" SortExpression="ProductName" />
                    <asp:BoundField DataField="SupplierID" HeaderText="SupplierID" SortExpression="SupplierID" />
                    <asp:BoundField DataField="CategoryID" HeaderText="CategoryID" SortExpression="CategoryID" />
                    <asp:BoundField DataField="QuantityPerUnit" HeaderText="QuantityPerUnit" SortExpression="QuantityPerUnit" />
                    <asp:BoundField DataField="UnitPrice" HeaderText="UnitPrice" SortExpression="UnitPrice" />
                    <asp:BoundField DataField="UnitsInStock" HeaderText="UnitsInStock" SortExpression="UnitsInStock" />
                    <asp:BoundField DataField="UnitsOnOrder" HeaderText="UnitsOnOrder" SortExpression="UnitsOnOrder" />
                    <asp:CheckBoxField DataField="Discontinued" HeaderText="Discontinued" SortExpression="Discontinued" />
                    <asp:BoundField DataField="ReorderLevel" HeaderText="ReorderLevel" SortExpression="ReorderLevel" />
                </Fields>
                <FooterStyle BackColor="Tan" />
                <HeaderStyle BackColor="Tan" Font-Bold="True" />
                <PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" HorizontalAlign="Center" />
            </asp:DetailsView>
            <br />
            <asp:LinkButton ID="LinkButton1" runat="server" PostBackUrl="~/Default.aspx">Go back</asp:LinkButton>
            <br />
            <br />

        </div>
        </form>
    </body>
    </html>

主页代码隐藏：

Partial Class _Default
    Inherits System.Web.UI.Page

    Protected Sub LinkButton1_Click(sender As Object, e As EventArgs) Handles LinkButton1.Click
        Dim product As New HttpCookie("product")
        product.Value = DropDownList1.SelectedValue
        product.Expires = DateTime.Now.AddHours(1)
        Response.Cookies.Add(product)
    End Sub
End Class

在Select Query中使用Cookie

0 个答案: