Nick blogged about why ASP.Net Repeaters Suck the other week and talked about using foreach loops in your .aspx.  I love this and have been doing it for a while – the strong typing and consice syntax is great.  However, sometimes I need format data based on odd and even rows…

 <table>

   <tr class='Row'><td></td></tr>

   <tr class='AltRow'>...</tr>

</table>

To accomplish this I created a helper function in the page code behind:

protected void Foreach<T>(IEnumerable<T> enumerable, Proc<T, int> action){

 int i = 0;

 foreach(T t in enumerable){

    action(t, i);

  i++

}

}

Then in the .aspx

<%Foreach(People, (person, i) => { %>

  <tr class='<%=i%2==0 ?  "Row" : "AltRow"%>'><td><%=person.FullName%></td></tr>

<%});%>

Just what I needed!