very simple question.

[alan123]

I have a variable say: $s=20, now I want to change it to string "0020", how can I do it in php? thanks.

 

[skiflyer]

Gotta be more specific... if you mean you want a zero padded four digit string...

$s = str_pad($s, '0', 4, STR_PAD_LEFT);

If you mean you want to pre-pend two zeros

$s = '00'.$s;

 

[DRJ478]

Here's a simple (and admitteldly stupid) answer. Please forgive me:

$s = 20;
$s = '0020';

The main contributor and master-expert of this forum, sleipnir214, has the following in his signature:

Want the best answers? Ask the best questions!

http://www.catb.org/~esr/faqs/smart-questions.html

 

[alan123]

Actually I need the fixed length string($a is a 4 character string), so

$a='00'.$s;

doesn't work, as $s may have only one or more characters.

I also tried:

$s = str_pad($s, '0', 4, STR_PAD_LEFT);

but I still get 20(two characters), it looks both ways are not working.

any suggestion?

thanks.

 

[sleipnir214]

If you need to output an integer as a four-digit string with whatever necessary leading zeros, I recommend that you use printf():

<?php
$a = 20;
printf ("%04u", $a);
?>





Want the best answers? Ask the best questions!

TANSTAAFL!!

 

[skiflyer]

Well I gave the right function, just swapped two arguments.

str_pad($s,4,'0',STR_PAD_LEFT);

Anyway, sleipnir's answer is also very good, and you may consider sprintf if it's the method you want but you want to assign the variable. rather than output it.

 

[alan123]

Thanks.