修改代码中的HTML表

Question

I have a table with a specific layout. It starts like this:

<table>
    <tr bgcolor="#007ACC" style="color:White">
        <td width="145"><asp:Label Text="" ID="lblLevel" runat="server" /></td><td width="80"></td><td width="30"></td><td width="145"><asp:Label Text="" ID="lblGroupNumber" runat="server" /></td><td width="60"></td><td width="10">Active</td>
    </tr>
    <tr>
        <td colspan="5"> 
            <asp:TextBox ID="txtName" runat="server" width="460px"></asp:TextBox>
        </td>
        <td> 
            <asp:DropDownList ID="cboActive" runat="server" Width="50px">
                <asp:ListItem>Y</asp:ListItem>
                <asp:ListItem>N</asp:ListItem>
            </asp:DropDownList>
        </td>
    </tr>

The problem is, under certain conditions I need it to look like this:

<table>
    <tr bgcolor="#007ACC" style="color:White">
        <td width="145"><asp:Label Text="" ID="lblLevel" runat="server" /></td><td width="80"></td><td width="30"></td><td width="145"><asp:Label Text="" ID="lblGroupNumber" runat="server" /></td><td width="60"></td><td width="10">Active</td>
    </tr>
    <tr>
        <td colspan="2">
            <asp:TextBox ID="txtName" runat="server" width="460px"></asp:TextBox>
        </td>
        <td></td>
        <td colspan="2"> 
            <asp:TextBox ID="txtNumber" runat="server" width="460px"></asp:TextBox>
        </td>
        <td> 
            <asp:DropDownList ID="cboActive" runat="server" Width="50px">
                <asp:ListItem>Y</asp:ListItem>
                <asp:ListItem>N</asp:ListItem>
            </asp:DropDownList>
        </td>
    </tr>

I've hidden textboxes before, that's no problem. But the only way I can think of to do this is to hide td's using code. I've seen this:

How to hide columns in HTML table?

but they never explain how you can determine which td is to be hidden.

So, can this be done in code (preferably code-behind in C#)? If so, how?

Answer 1

In asp.net most elements can be programmatically handled as server controls with runat set:

<td colspan="2" runat="server" id="tdToHide"> 
      <asp:TextBox ID="txtNumber" runat="server" width="460px"></asp:TextBox>
</td>

In C#:

tdToHide.Visible = false;

This is one of many, many approaches to 'hide things' on a web page.

Another one would be a conditional CSS class on the td . The display of which would then be dealt with by styles on the page.

Answer 2

You can use LiteralControl and then based on condition change the content or AddControl to the literalcontrol . This can be performed from code behind

Answer 3

Other way to select specific HTML Tags can bei done with css Selectors. http://www.w3schools.com/cssref/css_selectors.asp Look at etc.: p:nth-child(2)