<a id="cp-login" href="javascript:;" rel="#dialog" show="#login">登入</a>
$("a[id^=cp-][rel]").overlay(
{top: 120,mask: {color: '#67B300',loadSpeed: 200,opacity: 0.2},
closeOnClick: false,
onBeforeLoad: function() { alert($(this).attr("id") )}
});
alert($(this).attr("id")
未定义