php日期实例：取得上周，本周，上月，本月，本季度，上季度

<?php 
date_default_timezone_set('PRC'); 
date("Y-m-d H:i:s", strtotime(" +2 year")); 
date("Y-m-d H:i:s", strtotime(" +2 month")); 
date("Y-m-d H:i:s", strtotime(" +2 week")); 
date("Y-m-d H:i:s", strtotime(" +2 day")); 
date("Y-m-d H:i:s", strtotime(" +2 hour")); 
date("Y-m-d H:i:s", strtotime(" +2 minute")); 
date("Y-m-d H:i:s", strtotime(" +2 second")); 
 
echo date("Ymd",strtotime("now")), "n"; 
echo date("Ymd",strtotime("-1 week Monday")), "n"; 
echo date("Ymd",strtotime("-1 week Sunday")), "n"; 
echo date("Ymd",strtotime("+0 week Monday")), "n"; 
echo date("Ymd",strtotime("+0 week Sunday")), "n"; 
 
echo "*********第几个月:"; 
echo date('n'); 
echo "*********本周周几:"; 
echo date("w"); 
echo "*********本月天数:"; 
echo date("t"); 
echo "*********"; 
 
echo '<br>上周:<br>'; 
echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m"),date("d")-date("w")+1-7,date("Y"))),"n"; 
echo date("Y-m-d H:i:s",mktime(23,59,59,date("m"),date("d")-date("w")+7-7,date("Y"))),"n"; 
echo '<br>本周:<br>'; 
echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m"),date("d")-date("w")+1,date("Y"))),"n"; 
echo date("Y-m-d H:i:s",mktime(23,59,59,date("m"),date("d")-date("w")+7,date("Y"))),"n"; 
 
echo '<br>上月:<br>'; 
echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m")-1,1,date("Y"))),"n"; 
echo date("Y-m-d H:i:s",mktime(23,59,59,date("m") ,0,date("Y"))),"n"; 
echo '<br>本月:<br>'; 
echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m"),1,date("Y"))),"n"; 
echo date("Y-m-d H:i:s",mktime(23,59,59,date("m"),date("t"),date("Y"))),"n"; 
 
$season = ceil((date('n'))/3);//当月是第几季度 
 
echo '<br>本季度:<br>'; 
echo date('Y-m-d H:i:s', mktime(0, 0, 0,$season*3-3+1,1,date('Y'))),"n"; 
echo date('Y-m-d H:i:s', mktime(23,59,59,$season*3,date('t',mktime(0, 0 , 0,$season*3,1,date("Y"))),date('Y'))),"n"; 
 
$season = ceil((date('n'))/3)-1;//上季度是第几季度 
 
echo '<br>上季度:<br>'; 
echo date('Y-m-d H:i:s', mktime(0, 0, 0,$season*3-3+1,1,date('Y'))),"n"; 
echo date('Y-m-d H:i:s', mktime(23,59,59,$season*3,date('t',mktime(0, 0 , 0,$season*3,1,date("Y"))),date('Y'))),"n"; 
?>