CODEWITHSUNDEEP
php
puks1978
puks1978

Reputation: 3697

PHP preg_replace special characters

I am wanting to replace all non letter and number characters i.e. /&%#$ etc with an underscore (_) and replace all ' (single quotes) with ""blank (so no underscore).

So "There wouldn't be any" (ignore the double quotes) would become "There_wouldnt_be_any".

I am useless at reg expressions hence the post.

Cheers

Upvotes: 20

Views: 142585

Answers (3)

Chris Bornhoft
Chris Bornhoft

Reputation: 4291

$newstr = preg_replace('/[^a-zA-Z0-9\']/', '_', "There wouldn't be any");
$newstr = str_replace("'", '', $newstr);

I put them on two separate lines to make the code a little more clear.

Note: If you're looking for Unicode support, see Filip's answer below. It will match all characters that register as letters in addition to A-z.

Upvotes: 43

Filip Roséen
Filip Roséen

Reputation: 63797

If you by writing "non letters and numbers" exclude more than [A-Za-z0-9] (ie. considering letters like åäö to be letters to) and want to be able to accurately handle UTF-8 strings \p{L} and \p{N} will be of aid.

  1. \p{N} will match any "Number"
  2. \p{L} will match any "Letter Character", which includes
    • Lower case letter
    • Modifier letter
    • Other letter
    • Title case letter
    • Upper case letter

Documentation PHP: Unicode Character Properties

$data = "Thäre!wouldn't%bé#äny";

$new_data = str_replace  ("'", "", $data);
$new_data = preg_replace ('/[^\p{L}\p{N}]/u', '_', $new_data);

var_dump (
  $new_data
);

output

string(23) "Thäre_wouldnt_bé_äny"

Upvotes: 42

fardjad
fardjad

Reputation: 20394

do this in two steps:

  1. replace not letter characters with this regex:

    [\/\&%#\$]

  2. replace quotes with this regex:

    [\"\']

and use preg_replace:

$stringWithoutNonLetterCharacters = preg_replace("/[\/\&%#\$]/", "_", $yourString);
$stringWithQuotesReplacedWithSpaces = preg_replace("/[\"\']/", " ", $stringWithoutNonLetterCharacters);

Upvotes: 4

Related Questions