如何使用for或foreach循环运行DateTime来循环每天，并为每天添加+3天

Question

我在PHP中有两个日期，如何运行for或foreach循环来循环每一天，并为每一天添加+3天？

下面我添加了一个我想如何获得该列表的示例。

<?php
$begin = new DateTime( "2022-01-01" );
$end   = new DateTime( "2022-01-31" );
for($i=$begin; $i<=$end; $i->modify('+1 day')){    
for($j=$begin; $j<=$end; $j->modify('+3 day')){

echo $i->format("M d, Y").' => ';
echo $j->format("M d, Y").'<br/><br/>';

/*  I WANTS TO GET
* Jan 01, 2022 => Jan 04, 2022
* Jan 02, 2022 => Jan 05, 2022
* Jan 03, 2022 => Jan 06, 2022
*...
*...
* Jan 31, 2022 => Feb 03, 2022
*/
}    
}    
?>

Answer 1

如果结束日期总是离开始只有三天，那么在开始日期上只需要一个循环。然后，不需要第二个循环来设置结束日期，只需在每次迭代中相对于开始日期进行设置：

for ($start = $begin; $start <= $end; $start->modify('+1 day')) {    
$stop = clone $start;
$stop->modify('+3 days');
printf("%s => %sn", $start->format("M d, Y"), $stop->format("M d, Y"));
}

请注意，您需要通过克隆创建一个新的日期对象，这样您对+3 days的第二次修改就不会更改开始日期。

Answer 2

使用DateInterval()和DatePeriod()是设置参数和运行循环的简单情况

$begin = new DateTime( "2022-01-01" );
$end   = new DateTime( "2022-01-31" );
$interval = new DateInterval('P1D');
$daterange = new DatePeriod($begin, $interval ,$end);
foreach($daterange as $dateFrom){
$to = clone $dateFrom;
echo sprintf("%s => %sn", 
$dateFrom->format("M d, Y"), 
$to->modify('3 day')->format("M d, Y")
);  
}

结果

Jan 01, 2022 => Jan 04, 2022
Jan 02, 2022 => Jan 05, 2022
Jan 03, 2022 => Jan 06, 2022
Jan 04, 2022 => Jan 07, 2022
Jan 05, 2022 => Jan 08, 2022
Jan 06, 2022 => Jan 09, 2022
Jan 07, 2022 => Jan 10, 2022
Jan 08, 2022 => Jan 11, 2022
Jan 09, 2022 => Jan 12, 2022
Jan 10, 2022 => Jan 13, 2022
Jan 11, 2022 => Jan 14, 2022
Jan 12, 2022 => Jan 15, 2022
Jan 13, 2022 => Jan 16, 2022
Jan 14, 2022 => Jan 17, 2022
Jan 15, 2022 => Jan 18, 2022
Jan 16, 2022 => Jan 19, 2022
Jan 17, 2022 => Jan 20, 2022
Jan 18, 2022 => Jan 21, 2022
Jan 19, 2022 => Jan 22, 2022
Jan 20, 2022 => Jan 23, 2022
Jan 21, 2022 => Jan 24, 2022
Jan 22, 2022 => Jan 25, 2022
Jan 23, 2022 => Jan 26, 2022
Jan 24, 2022 => Jan 27, 2022
Jan 25, 2022 => Jan 28, 2022
Jan 26, 2022 => Jan 29, 2022
Jan 27, 2022 => Jan 30, 2022
Jan 28, 2022 => Jan 31, 2022
Jan 29, 2022 => Feb 01, 2022
Jan 30, 2022 => Feb 02, 2022

Answer 3

如果您愿意，也可以对所有对象使用相同的DateTime对象。

for ($i = $begin; $i <= $end; $i->modify('-2 day')) {
echo $i->format("M d, Y") . ' => ';
echo $i->modify('+3 day')->format("M d, Y") . '<br><br>';
}