Question

I store some error_log with date for their name. like 20120827.txt

Now I write some php script for view the error_log.

I need do some judgment:

if(file_exists(date("Ymd").'.txt')){ 
   $html = file_get_contents(date("Ymd").'.txt');
}else{
   $html = file_get_contents((date("Ymd")-1).'.txt');//load yesterday's `error_log`.
}

But this not suit the date like 20120801.txt, How to do date("Ymd")-1?

I tried date("Ymd", (strtotime($date) . " -1 day"));// return:19700101

Answer 1

If you want yesterday’s date you can do

date("Ymd", time() - 3600*24);

Or you could use the DateTime object:

$date = new DateTime();
$date->modify("-1 day");
echo $date->format("Ymd");