RegEx To Validate 4 and 5 Digit Numbers?

Question

I have this regex :

if(preg_match("@^\d{4}$@", basename($entry, ".php"))) {
--do something here--
}

that condition works only for 4 digits number. but I need to validate 4 digits and also 5 digits. how to make it work to validate 5 digits number too? thanks!

* See also [Open source RegexBuddy alternatives](http://stackoverflow.com/questions/89718/is-there) and [Online regex testing](http://stackoverflow.com/questions/32282/regex-testing) for some helpful tools, or [RegExp.info](http://regular-expressions.info/) for a tutorial. — mario, Nov 07 '12 at 16:32

score 6 · Accepted Answer · answered Nov 07 '12 at 16:28

6

the braces can take a low and high end of a range so {4,5} should work.

answered Nov 07 '12 at 16:28

LazyMonkey

517
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+1 for the regular expression explanation. I encourage you to also provide a code sample. – Jason McCreary Nov 07 '12 at 16:38
Here's something you can run on the command line: `php -r '$pattern = "/^\d{4,5}/"; preg_match($pattern, "12345678", $a); print_r($a);'` – LazyMonkey Nov 07 '12 at 19:13

score 3 · Answer 2 · answered Nov 07 '12 at 16:30

3

As an alternative to Regular Expressions, consider simpler functions like ctype_digit() and strlen().

$filename = basename($entry, ".php");
$length = strlen($filename);

if (($length >= 4 && $length <= 5) && ctype_digit($filename)) {
  // your code
}

answered Nov 07 '12 at 16:30

Jason McCreary

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score 2 · Answer 3 · answered Nov 07 '12 at 16:29

2

if(preg_match("@^\d{4,5}$@", basename($entry, ".php"))) {
--do something here--
}

answered Nov 07 '12 at 16:29

Pedro del Sol

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score 2 · Answer 4 · answered Nov 07 '12 at 16:29

2

instead of

 if(preg_match("@^\d{4}$@", basename($entry, ".php"))) {

use

if(preg_match("@^\d{4,5}$@", basename($entry, ".php"))) {

answered Nov 07 '12 at 16:29

exussum

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8
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RegEx To Validate 4 and 5 Digit Numbers?

4 Answers4