PHP quotemeta() Function: Syntax, Usage, and Replacement with preg_quote()

quotemeta() Function Syntax

<code>string quotemeta(string $str)</code>

Parameter Description

$str : required, the string to be escaped.

Return Value

Returns the escaped string.

Function Description

The quotemeta() function escapes special characters in the given string so they are treated as literal characters in a regular expression. The characters escaped are: . , * , + , ? , [ , ^ , $ , ( , ) , { , } , | , \ , and / .

Notes

The quotemeta() function was deprecated after PHP 5.3.0 and removed in PHP 7.0.0. It is recommended to use the preg_quote() function instead.

Usage Example

<code><?php
$str = "Hello.* World+?";
echo quotemeta($str); // Output: Hello\.\*\ World\+\?
?>
</code>

In this example, the string "Hello.* World+?" is passed to quotemeta() , which escapes the characters . , * , + , and ? , producing "Hello\.\*\ World\+\?".

preg_quote() Alternative

Since quotemeta() is deprecated, the preg_quote() function is recommended as a replacement. preg_quote() can escape the same characters as quotemeta() and also additional regex special characters.

Example Using preg_quote()

<code><?php
$str = "Hello.* World+?";
echo preg_quote($str); // Output: Hello\.\*\ World\+\?
?>
</code>

This example shows that preg_quote() produces the same escaped result as quotemeta() for the given string.

Summary

The PHP quotemeta() function is used to escape special characters in a string for regular expressions, but it has been deprecated and removed; therefore, the preg_quote() function is recommended as a more comprehensive alternative.