for，以四个零递增

Question

$second= 3113;
for ($i = 0000; $i < 7000; $i += 100) { 
     $a=$second.$i;// 31130
     ...
}

This will output:

31130
3113100
3113200

What I need:

31130000 
31130100 
31130200 

How do you solve this?

Answer 1

Numbers will always be shown with zeroes trimmed. You can force a certain number of zeroes with sprintf like so:

$a = $second.sprintf("%04s",$i); // 31130000