如何用+1增加一个数字，保留0？

In php, when I increment:

$numb = "00001";
$numb = $numb +1;

The result is 2.

How do I keep the zeroes and having 00002 ?

Useful link for BASH and for JAVA but not able to think of a php version.

Thank you!

Try this:

$numb = "00001";
$numb = $numb +1;
echo str_pad($numb, 5, '0', STR_PAD_LEFT);