For the last few hours, I've been trying to figure out why my event handler is not being hooked up when I hit the ENTER key to submit my ASP.NET form.
As it turns out, this is a bug with ASP.NET. If you're not aware of this, the work around is to insert an invisible HTML textbox (an asp:TextBox wont work).
Add this line somewhere on the page:
<input type="text" style="display:none"/>
and all will work as expected.