How to add a <td> tag to ListViewItem?

Question

I want to implement an apperance as this article mentioned using nested ListView control. However, in my scenario, I cannot use EntityDataSource control so I bind data manually.

My table:

Categories
  PK: UniqueId, Guid
  Name, string
  ParentId, Guid

<asp:ListView ID="CategoryList" runat="server" 
        onitemdatabound="CategoryList_ItemDataBound">
        <LayoutTemplate>
            <table>
                <asp:PlaceHolder ID="itemPlaceHolder" runat="server"></asp:PlaceHolder>
            </table>
        </LayoutTemplate>

        <ItemTemplate>
            <tr>
                <td colspan="2"><%# Eval("Name") %></td>
            </tr>
        </ItemTemplate>
    </asp:ListView>



protected void Page_Load(object sender, EventArgs e)
{
    using (PractiseEntities context = new PractiseEntities()) {
        var result = from categories in context.Categories
                     select categories;
        CategoryList.DataSource = result;
        CategoryList.DataBind();
    }
}

I want the sub category have an indent by add a <td> tag to the item which "ParentId" is not null. And my question is how to edit the generated html tags in the ItemDataBound event?

Answer 1

You could have something like this:

<ItemTemplate>
    <tr>
        <td colspan="2"><%# GetParentContent(Eval("ParentID")) %></td>
    </tr>
</ItemTemplate>

in the code-behind:

protected string GetParentContent(object ParentID)
{
    if(ParentID!=null)
        ... return parent HTML ...
    else
        return "";
}