常见代码

方式一

$year = date("Y");
$month = date("m");
$day = date("d");
$dayBegin = mktime(0,0,0,$month,$day,$year);//当天开始时间戳

方式二:

$daybegin=strtotime(date("Ymd"));

参考

http://www.cnblogs.com/wangtao_20/archive/2011/01/06/1929046.html http://blog.csdn.net/dongsg11200/article/details/8988598