上一页的值未传输

Question

我有以下代码，其中我试图将前一页的文本框控件（位于母版页中）中的一些文本传输到同一个母版页文本框控件。但是它不起作用。如果您能发现错误，请告诉我。

  protected void Page_Load(object sender, EventArgs e)
    {


        if (PreviousPage != null)
        {
            TextBox placeholder =
                (TextBox)PreviousPage.Master.FindControl("TextBox1");
            if (placeholder != null)
            {
                TextBox searchBox = (TextBox)Master.FindControl("TextBox1");
                string search = placeholder.Text.ToString();
                searchBox.Text = search;
            }
        }
    }

这是主页的 .aspx：

<%@ Master Language="C#" AutoEventWireup="true" CodeBehind="Site1.master.cs" Inherits="AlexBookShop.Site1" %>

<!DOCTYPE html>

<html>
<head runat="server">
    <title></title>
    <asp:ContentPlaceHolder ID="head" runat="server">
    </asp:ContentPlaceHolder>
    <style type="text/css">
        .auto-style1 {
            margin-bottom: 0px;
        }
    </style>
</head>
<body>


    <form id="form1" runat="server">


        <div>

            <asp:DropDownList ID="DropDownList1" runat="server">
                <asp:ListItem Value="1">Children</asp:ListItem>
                <asp:ListItem Value="1">Finance</asp:ListItem>
                <asp:ListItem Value="3">Non-Fiction</asp:ListItem>
                <asp:ListItem Value="4">Technical</asp:ListItem>
            </asp:DropDownList>

            <asp:TextBox ID="TextBox1" runat="server" CssClass="auto-style1"></asp:TextBox>
            <asp:Button ID="Button1" runat="server" Text="Search" OnClick="Button1_Click" />
            <asp:Button ID="Button2" runat="server" Text="Log Out" OnClick="Button2_Click" />

            <asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server">
            </asp:ContentPlaceHolder>
        </div>

    </form>

</body>
</html>

Answer 1

要通过 MasterPAge 将数据从一页传输到另一页，您需要执行 cross page posting。

您需要将第一页上的button控件的PostBackUrl属性指定为指向第二页。喜欢

<asp:Button ID="Button1" runat="server" Text="Button" PostBackUrl="~/Secondpage.aspx"/>
在第二页设置 PreviousPage 指令：

<%@ PreviousPageType VirtualPath="~/firstpage.aspx" %>

然后每当第二页收到回发时，从第一页获取您需要的数据：

protected void Page_Load(object sender, EventArgs e)
{
    if (PreviousPage != null)
    {
        TextBox placeholder =
            (TextBox)PreviousPage.Master.FindControl("TextBox1");
        if (placeholder != null)
        {
            TextBox searchBox = (TextBox)Master.FindControl("TextBox1");
            string search = placeholder.Text.ToString();
            searchBox.Text = search;
        }
    }
}

上一页的值未传输

Value from previous page not transferring

asp.net

webforms

master-pages