wp_has_noncharacters() │ WP 6.9.0

Returns whether the given string contains Unicode noncharacters.

XML recommends against using noncharacters and HTML forbids their use in attribute names. Unicode recommends that they not be used in open exchange of data.

Noncharacters are code points within the following ranges:

U+FDD0–U+FDEF
U+FFFE–U+FFFF
U+1FFFE, U+1FFFF, U+2FFFE, U+2FFFF, …, U+10FFFE, U+10FFFF

No Hooks.

Returns

bool. Whether noncharacters were found in the string.

Usage

wp_has_noncharacters( $text ): bool;

$text(string) (required): Are there noncharacters in this string?.

Notes

See: https://www.unicode.org/versions/Unicode17.0.0/core-spec/chapter-23/#G12612

See: https://www.w3.org/TR/xml/#charsets

See: https://html.spec.whatwg.org/#attributes-2

Changelog

Since 6.9.0

Introduced.

`wp_has_noncharacters() wp has noncharacters` code ^{WP 7.1}

wp-includes/utf8.php

function wp_has_noncharacters( string $text ): bool {
	/*
	 * Match the UTF-8 byte sequences directly so malformed UTF-8 elsewhere
	 * in the subject does not cause PCRE's Unicode mode to reject the string.
	 */
	return 1 === preg_match(
		'~
			# U+FDD0-U+FDEF, U+FFFE-U+FFFF
			\xEF(?:\xB7[\x90-\xAF]|\xBF[\xBE\xBF])
			|
			# U+nFFFE/U+nFFFF
			(?:\xF0[\x9F\xAF\xBF]|[\xF1-\xF3][\x8F\x9F\xAF\xBF]|\xF4\x8F)\xBF[\xBE\xBF]
		~x',
		$text
	);
}