preg_match
If you need to quote everything but a wildcard, maybe this function will come handy to you:
<?php
protected function _ruleOptionIsMatched($option, $subject)
{
$option = preg_quote($option, '#');
$option = str_replace('\*', '.*', $option);
if(preg_match("#^$option$#", $subject))
{
return true;
}
else
{
return false;
}
}
?>
preg_quote
(PHP 4, PHP 5)
preg_quote — 정규 표현식 문자를 인용
설명
string preg_quote
( string $str
[, string $delimiter
] )
preg_quote()는 str에서 정규 표현식 문법에 포함되는 모든 문자의 앞에 백슬래시를 덧붙입니다. 어떠한 텍스트에 특수 정규 표현식 문자를 포함하는 런타임 문자열을 처리할 때 유용합니다.
정규 표현식 특수 문자는: . \ + * ? [ ^ ] $ ( ) { } = ! < > | :
인수
- str
-
입력 문자열.
- delimiter
-
delimiter를 정의하면, 그 문자들도 이스케이프합니다. PCRE 함수에서 요구하는 구분자를 이스케이프 할 때 유용합니다. /는 가장 널리 사용되는 구분자입니다.
반환값
인용한 문자열을 반환합니다.
예제
Example #1 preg_quote() 예제
<?php
$keywords = '$40 for a g3/400';
$keywords = preg_quote($keywords, '/');
echo $keywords; // \$40 for a g3\/400 를 반환합니다.
?>
Example #2 텍스트 안의 단어를 기울임꼴로
<?php
// 이 예제에서, preg_quote($word)는 정규 표현식에서
// 특별한 의미를 지니는 애스터라이크(*)의 처리에 사용됩니다.
$textbody = "This book is *very* difficult to find.";
$word = "*very*";
$textbody = preg_replace("/" . preg_quote($word) . "/",
"<i>" . $word . "</i>",
$textbody);
?>
주의
Note: 이 함수는 바이너리 안전입니다.
add a note
User Contributed Notes
preg_quote - [9 notes]
billadoid at gmail dot com ¶
1 year ago
Anonymous ¶
5 years ago
Wondering why your preg_replace fails, even if you have used preg_quote?
Try adding the delimiter / - preg_quote($string, '/');
bizzigul at hotmail dot fr ¶
4 years ago
To prevent any problems, try to always use a delimiter that will *almost* not be used inside the regex, such as ` (back quote)
for example: instead of
<?php preg_match('/foo\/bar\//',$somevar); ?>
use
<?php preg_match('`foo/bar/`',$somevar); ?>
it's that simple! like this, you won't have to bother with delimiters anymore...
zooly ¶
3 years ago
To escape characters with special meaning, like: .-[]() and so on, use \Q and \E.
For example:
<?php echo ( preg_match('/^'.( $myvar = 'te.t' ).'$/i', 'test') ? 'match' : 'nomatch' ); ?>
Will result in: match
But:
<?php echo ( preg_match('/^\Q'.( $myvar = 'te.t' ).'\E$/i', 'test') ? 'match' : 'nomatch' ); ?>
Will result in: nomatch
krishoog at gmail dot com ¶
4 years ago
To bizzigul at hotmail dot fr:
It's not a good practice to make somthing work *almost* all of the time. If the input contains a '`' you will still get an error. I recommend using the default delimiter ('/') and also feed this to preg_quote as second argument.
php at richardneill dot org ¶
2 months ago
preg_quote() only works on the search string, not the replacement string.
But the replacement string isn't always literal, as it can contain backreferences.
There's no function to quote the replacement string, but a workaround is to escape all $ and \ signs:
$replace = str_replace (array('\\','$'),array('\\\\','\$'),$replace);
For example:
$text = 'Test: *#5*';
$search = "*#5*";
$replace = "*$5\\1*";
$search = preg_quote($search, "/");
$replace = str_replace (array('\\','$'),array('\\\\','\$'),$replace);
$new = preg_replace("/$search/", "$replace", $text);
echo "Input: $text\nOutput: $new\n";
Prints:
Input: Test: *#5*
Output: Test: *$5\1*
admin at nilamo dot com ¶
2 years ago
@zooly:
And what if $myvar = 'te\\E.t'? It will match, when it shouldn't. That's why you should use preg_quote().
alexc223 at NOSPAM dot googlemail dot com ¶
4 years ago
Not sure why this note got deleted, but hey lets try again:
As of PHP 5.3, bug #47229 has been fixed and preg_quote *will* escape a hyphen (-). This may effect your code so ensure this is one thing you check when moving to 5.3.
frostschutz ¶
4 years ago
I wanted to escape a string of characters so I could match them in [], i.e. [.,-!"§$%\\\[\]\^].
Unfortunately preg_quote does not escape the - character which has a special meaning in [], i.e. [a-z].
So I used this hack: make - the delimiter of the expression, i.e.
preg_quote(userinput, "-")
preg_replace("-[$userinput]-u", "", $str)
Apparently using a special char as a delimiter of a regular expression disables this character, i.e. even if it's escaped it's not understood as special character for the expression anymore.
so the pattern "-[a\\-z]-u" matches the characters a, - and z, and not abc...xyz.
It would be nice if preg_quote also escaped characters that have special meanings even if they have this meaning only under certain conditions, such as inside [].