这是我的数组
$array = array(
"13111" => "2014-06-21 19:51:00.0000000",
"23111" => "2014-06-20 19:51:00.0000000",
"12111" => "2014-06-21 19:51:00.0000000",
"23311" => "2014-06-22 19:51:00.0000000",
"13114" => "2014-06-21 19:51:00.0000000",
"23711" => "2014-06-20 19:51:00.0000000",
);
如何获取数组的前3个元素以及如何按日期时间排序?感谢