html - 如何在 ASPX 页面中引用 DOM 中的父元素？

Question

这是我的页面片段：

...
<asp:Content ID="Main" ContentPlaceHolderID="PlaceHolderMain" runat="server">
  <table>
    <tr>
      <td>
        <asp:TextBox MaxLength="255" ID="myTextBox" runat="server"></asp:TextBox>
      </td>
    </tr>
  </table>
</asp:Content>
...

这是页面代码隐藏部分：

...
Control parent = this.myTextBox.Parent; //this is acutally asp:Content control
string parentID = parent.ID; //this is PlaceHolderMain
...

我需要的是引用<td>元素（因为我想改变它的Visibility属性）。我怎样才能做到这一点？我哪里错得这么严重？:)

Answer 1

td needs to be ran server side for it to be accessed and classed as a parent element.

<td id="td" runat="server">
   <asp:TextBox MaxLength="255" ID="myTextBox" runat="server"></asp:TextBox>
</td>

Answer 2

ASPX Code behind really only knows about the ASP controls (i.e. the ones with the asp: prefix in the tags) the td is just plain old html. In order for the code behind to interacte with it, you will need to add a runat="server" on the tag

Answer 3

The table over here is an html table not an ASP.NET server control. So you can't access it in the code behind.

Use this in case :

<asp:Table ID="Table1" runat="server">
            <asp:TableRow ID="TableRow1" runat="server" ForeColor="Teal">
                <asp:TableCell>
                    <asp:TextBox MaxLength="255" ID="myTextBox" runat="server"> 
                    </asp:TextBox>
                </asp:TableCell>
            </asp:TableRow>
</asp:Table>

Answer 4

<td>按照其他用户的建议，将属性 runat 添加到标记。

<td id="mytd" runat="server">
   <asp:TextBox MaxLength="255" ID="myTextBox" runat="server"></asp:TextBox>
</td>

然后在c#端（返回页面）

添加这个头文件

using System.Web.UI.HtmlControls;
protected void Button_click(object sender,EventArgs e)
{
  mytd.Attributes.Add("style","visibility:none");
}