php如何把日期转换成秒

<?phplist($year,$month,$day,$hour,$minute,$second)=split ("[-: ]","2007-9-22 20:10:12");//通过split函数分别把2007,9,22存入$year,$month,$day,$hour,$minute,$second六个参数中$seconds=mktime($hour,$minute,$second,$month,$day,$year);//根据年 月 日 时 分 秒输出时间戳echo $seconds;//获取指定日期是$weekarray=array("日","一","二","三","四","五","六");$day= strtotime("2013-01-18"); echo "星期".$weekarray[date("w",$day)];