Change repeater li item class if first or last

Question

I'm using repeater to create dynamic ul li list

Is it possible to control class whether item is first or last?

Something like:

class="<%# if(Container.ItemIndex == 0)    {         class = ...     }    ) %>" 

by the way what does it really mean: <%# in ASP.NET

What is the difference between <%# and <%=?

Answer 1

It is quite easy to determine whether the item is first or not (Container.ItemIndex == 0), but to determine whether the element is last or not you have to use a custom property which will be initialized right with data binding:

protected int ItemCount { get; set; } 

Here is a repeater example:

<asp:Repeater runat="server" ID="repeater">     <HeaderTemplate>         <ul>     </HeaderTemplate>     <ItemTemplate>         <li class="<%# GetItemClass(Container.ItemIndex) %>">             <%# Container.DataItem %>         </li>     </ItemTemplate>     <FooterTemplate>         </ul>     </FooterTemplate> </asp:Repeater> 

here is an example of data binding:

public override void DataBind() {     var data = new string[] { "first", "second", "third" };     this.ItemCount = data.Length;      repeater.DataSource = data;     repeater.DataBind(); } 

and finally a helper method:

protected string GetItemClass(int itemIndex) {     if (itemIndex == 0)         return "first";     else if (itemIndex == this.ItemCount - 1)         return "last";     else         return "other"; } 

This will produce:

<ul>     <li class="first">         first     </li>     <li class="other">         second     </li>     <li class="last">         third     </li> </ul> 

Answer 2

I typically use something like the following:

<asp:Repeater ID="rptItems" runat="server" ViewStateMode="Disabled">   <ItemTemplate>     <li<%# Container.ItemIndex == ((IList)((Repeater)Container.Parent).DataSource).Count-1 ? " class='last'" : ""%>> ...     </li>   </ItemTemplate> </asp:Repeater>