asp.net - asp:repeater - headers at section change

Question

is there any way to bring up a subheader row at changes in a field in an databound asp:repeater control e.g.

Instead of

country | colour | number
uk | red | 3
uk | green | 3
france | red 3

Do this:

==UK==
colour | number
red | 3
green 3
==FRANCE==
colour | number
red | 3

Many thanks for any help.

Answer 1

There's no built-in support, but that doesn't mean it's impossible.

You'll need to over-ride the OnItemDataBound event, and have something like this in markup:

<asp:Repeater OnItemDataBound="NextItem" ... >
    <ItemTemplate><asp:Literal Id="Header" Visible="False" Text="{0}<strong>{1}</strong><br/><table>" ... />
         <tr>
             <td><asp:Label id="Color" Text="<%# Eval("Color")" ... /></td>
             <td><asp:Label id="Number" Text="<%# Eval("Number")" ... /></td>
         </tr>
    </ItemTemplate>
</asp:Repeater></table>

Then in the code-behind:

private string CurCountry = string.Empty;

private void NextItem(object sender, RepeaterItemEventARgs e)
{
    if ( e.Item.ItemType != ListItemType.Item 
      && e.Item.ItemType != ListItemType.AlternatingItem) return;

    DbDataRecord row = (DbDataRecord)e.Item.DataItem;

    if (CurCountry != row["country"].ToString() )
    {
        string prev = (CurCounter == string.Empty)?"":"</table>";
        CurCountry = row["country"].ToString();

        Literal header = (Literal)e.Item.FindControl("Header");
        Literal footer = (Literal)e.Item.FindControl("Footer");

        header.Text = string.Format(header.Text, prev, CurCountry);
        header.Visible = true;
    }
}