PHPの日付処理コード

echo "";echo date("Y-m-d",strtotime("now")), "n";echo "";echo date ("Y-m-d",strtotime("-1 週間の月曜日")), "n";echo "";echo date("Y-m-d",strtotime("-1 週間の日曜日")), "n ";echo "";echo date("Y-m-d",strtotime("+0 週月曜日")), "n";echo "";echo date("Y-m-d" ,strtotime("+0 週の日曜日")), "n";echo ""; echo "*********第几个月:";echo date('ん'); echo "";echo "*********本周几:";echo date("w"); echo "";
echo "*********本月天数:";
echo date("t");
 
echo ""; echo ' 上周:';
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 "";
echo '本周: ';
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 "";
echo '上上月:';
echo date( "Y-m-d H:i:s",mktime(0, 0 , 0,date("m")-2,1,date("Y"))),"n";
echo date("Y-m-d H:i :s",mktime(23,59,59,date("m")-1,0,date("Y"))),"n";
echo "";
 
echo '< ;br>上月:';
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 "";
echo '今月:';
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";
echo "";
 
echo "";
$season = ceil((date('n'))/ 3)-2;//上季度は第几季度
echo '上上季度:';
echo date('Y-m-d H:i:s', mktime(0, 0, 0 ,$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"; 
 echo "";
 
echo "";
$season = ceil((date('n'))/3)-1;// 上季度是第几季度
echo ' 上季度:';
echo date('Y-m-d H:i:s', mktime(0, 0, 0,$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"; 
 echo "";
 
echo $season = ceil((date('n'))/3);//当月は第几季度
echo '本季度: ';
echo date('Y-m-d H:i:s', mktime(0, 0, 0,$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";
 
$season = ceil((date('n'))/3)+1;//当月是第几季度
echo '';
echo date('Y-m-d H:i:s', mktime(0, 0, 0,$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";
 
echo ""; ?>

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