PHP preg_quote() Function
Example
Use preg_quote() to safely use special characters in a regular expression:
<?php
$search = preg_quote("://", "/");
$input = 'https://www.w3schools.com/';
$pattern = "/$search/";
if(preg_match($pattern, $input)) {
echo
"The input is a URL.";
} else {
echo "The input is not a URL.";
}
?>
Try it Yourself »
Definition and Usage
The preg_quote() function adds a backslash to characters that have a special meaning in
regular expressions so that searches for the literal characters can be done. This function is
useful when using user input in regular expressions.
Syntax
preg_quote(input, delimiter)
Parameter Values
| Parameter | Description |
|---|---|
| input | Required. The string to be escaped |
| delimiter | Optional. Defaults to null. This parameter expects a single character indicating which delimiter the regular expression will use. When provided, instances of this character in the input string will also be escaped with a backslash |
Technical Details
| Return Value: | Returns a string with all of the special characters escaped with a backslash |
|---|---|
| PHP Version: | 4+ |
| Changelog: | PHP 7.3 - The # character is now considered a special character and will be escaped. PHP 5.3 - The - character is now considered a special character and will be escaped. |
❮ PHP RegExp Reference
