zerofill a integer php

Question

How would I go about 'zero filling' an integer?

ie

1 becomes 0001
40 becomes 0040
174 becomes 0174

Solution 1

$filled_int = sprintf("%04d", $your_int)

Solution 2

$number = 12;
$width = 4;
$padded = str_pad((string)$number, $width, "0", STR_PAD_LEFT); 

Comments

[Tom Haigh]

This pads to the right of the number, and pads with spaces not zeros. $padded = str_pad($number, $width, 0, STR_PAD_LEFT);

[Joe]

Yeah, ommission on my part. Corrected. But I would retain some semblance of type safety by providing appropriate types (even if conversion is automatic).

[Jack Henahan]

Depending on the scenario, I'd say this is usually the better solution. Additionally, it is not currently necessary to explicitly cast to string unless you use a numeric literal in str_pad. A variable of a numeric type will be implicitly cast.

[Nuri Akman]

If you want to Zero Pad for 15 digits, should be like this: $filled_int = sprintf("%015d", $your_int)