Home/ Questions/Q 647413
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-13T21:43:10+00:00

if (preg_match(‘(\p{Nd}{4}/\p{Nd}{2}/\p{Nd}{2}/\p{L}+)’, ‘2010/02/14/this-is-something’)) { // do stuff } The above code works. However this

  • 0
if (preg_match('(\p{Nd}{4}/\p{Nd}{2}/\p{Nd}{2}/\p{L}+)', '2010/02/14/this-is-something'))
{
  // do stuff
}

The above code works. However this one doesn’t.

if (preg_match('/\p{Nd}{4}/\p{Nd}{2}/\p{Nd}{2}/\p{L}+/u', '2010/02/14/this-is-something'))
{
    // do stuff
}

Maybe someone could shed some light as to why the one below doesn’t work. This is the error that is being produced:

A PHP Error was encountered

Severity: Warning

Message: preg_match()
[function.preg-match]: Unknown
modifier ‘\’

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    The modifier u is available from PHP 4.1.0 or greater on Unix and from PHP 4.2.3 on win32.

    Also as nvl observed, you are using / as the delimiter and you are not escaping the / present in the regex. So you’lll have to use:

    /\p{Nd}{4}\/\p{Nd}{2}\/\p{Nd}{2}\/\p{L}+/u

    To avoid this escaping you can use a different set of delimiters like:

    #\p{Nd}{4}/\p{Nd}{2}/\p{Nd}{2}/\p{L}+#

    or

    @\p{Nd}{4}/\p{Nd}{2}/\p{Nd}{2}/\p{L}+@

    As a tip, if your delimiter is present in your regex, its better to choose a different delimiter not found in the regex. This keeps the regex clean and short.

    • 0