strtotime未能及时增加30天

Question

我的代码是：

$result = 20201601; //fetched from a source as string

//Convert string to date format 'Y/m/d'

$date1 = substr($result, 0, 4) . '/' . substr($result, 4, 2) . '/' . substr($result, 6, 2); 

echo $date1 . "<br>";

//Add 30 days to it

$date2 = date('Y/m/d', strtotime('+30 days', strtotime($date1)));

echo $date2;

if ($date2 < date('Y/m/d', strtotime('now')))

{

    //If date fetched ($result) is older than 30 days from today's date, then fetch new date from source

}

代码无法在以下位置添加 30 天：，它给出：date('Y/m/d', strtotime('+30 days', strtotime($date1)))1970/01/30

Answer 1

改变$date1&nbsp;=&nbsp;substr($result,&nbsp;0,&nbsp;4)&nbsp;.&nbsp;'/'&nbsp;.&nbsp;substr($result,&nbsp;4,&nbsp;2)&nbsp;.&nbsp;'/'&nbsp;.&nbsp;substr($result,&nbsp;6,&nbsp;2);自$date1&nbsp;=&nbsp;substr($result,&nbsp;0,&nbsp;4)&nbsp;.&nbsp;'/'&nbsp;.&nbsp;substr($result,&nbsp;6,&nbsp;2)&nbsp;.&nbsp;'/'&nbsp;.&nbsp;substr($result,&nbsp;4,&nbsp;2);这是必需的，因为您当前的数据的格式为 。一个月不能有值。2020160116