preg_quote

preg_quote

Quote regular expression characters

string **preg_quote** string $str  $delimiter

takes 

and puts a backslash in front of every character that is part of the regular expression syntax. This is useful if you have a run-time string that you need to match in some text and the string may contain special regex characters. preg_quote``str

The special regular expression characters are:

. \ + * ? [ ^ ] $ ( ) { } = ! < > | : - #

Note that is not a special regular expression character. /

Opmerking: > Note that is not meant to be applied to the $replacement string(s) of etc. preg_quote``preg_replace

strThe input string.

delimiter If the optional is specified, it will also be escaped. This is useful for escaping the delimiter that is required by the PCRE functions. The is the most commonly used delimiter. delimiter``/

Returns the quoted (escaped) string.

Voorbeeld: example

<?php
$keywords = '$40 for a g3/400';
$keywords = preg_quote($keywords, '/');
echo $keywords; // returns \$40 for a g3\/400
?>

Voorbeeld: Italicizing a word within some text

<?php
// In this example, preg_quote($word) is used to keep the
// asterisks from having special meaning to the regular
// expression.

$textbody = "This book is *very* difficult to find.";
$word = "*very*";
$textbody = preg_replace ("/" . preg_quote($word, '/') . "/",
                          "<i>" . $word . "</i>",
                          $textbody);
?>

PCRE Patternsescapeshellcmd