字符串转为日期对象
IE8、Chrome、猎豹6有效，其它未测试
var timestr = "2017-05-15T09:30:21Z";
timestr = timestr.replace(/(\d{4})-(\d{2})-(\d{2})T(.*)?/, "$1/$2/$3 $4");
new Date(timestr)
var timestr = '2014-02-26T21:18:02.497'
var timestr = timestr .replace(/(\d{4})-(\d{2})-(\d{2})T(.*)?\.(.*)/, "$1/$2/$3 $4")
new Date(timestr )