php - 如何在 PHP 中减去两个日期并在没有交互的情况下发送自动电子邮件

Question

我想减去两个日期，这样只会相差 15 天，然后在没有用户交互的情况下自动发送电子邮件？这怎么可能？

这是我的 PHP 代码

<?php

$user = 'root';
$pass = '';
$con = 'pharmacy';
$con = new mysqli('127.0.0.1', $user, $pass, $con);

if(!$con)
{
echo 'Unable to Connect with Server';
}
if (!mysqli_select_db($con,'pharmacy'))
{
echo 'Database is Not Selected';
}
//select database
mysqli_select_db($con,'pharmacy');

//Expiry Date which is stored in Datebase 
//Convert String into Date Format
$sql_unique=$con->query("SELECT exp_dt FROM scandrug");
$expiry = strtotime($sql_unique);
$newformat = date('d-m-Y',$expiry);

$day= date('d',$newformat);   //Day of the month
$month= date('m',$newformat); //Month of the year
$year= date('Y',$newformat);  //Year

//echo $newformat;

//Obtain current Date
$current_dt = new DateTime();
$current_dt= date('d-m-Y');

$dayy= date('d',$current_dt);  //Day of the month
$monthh= date('m',$current_dt); //Month of the year
$yearr= date('Y',$current_dt);  //Year

//echo $current_dt;
do{
if($day-$dayy==15 || $day-$dayy==-15 && $month-$monthh==01 || $month-$monthh==00 && $year-$yearr==0000)
{

}
else
{
//nothing will happen
}
}while(1);
?>

Answer 1

只需尝试这个即可找到两个日期之间的差异，然后按照您的需要进行操作

$datetime1 = new DateTime('2009-10-11');
$datetime2 = new DateTime('2009-10-13');
$interval = $datetime1->diff($datetime2);
echo $interval->format('%R%a days');