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wp_kses_normalize_entities3() WP 2.7.0

Callback for wp_kses_normalize_entities() for regular expression.

This function helps wp_kses_normalize_entities() to only accept valid Unicode numeric entities in hex form.

No Hooks.

Return

String. Correctly encoded entity.

Usage

wp_kses_normalize_entities3( $matches );
$matches(array) (required)
preg_replace_callback() matches array.

Code of wp kses normalize entities3: wp-includes/kses.php WP 5.2.1

<?php
function wp_kses_normalize_entities3( $matches ) {
	if ( empty( $matches[1] ) ) {
		return '';
	}

	$hexchars = $matches[1];
	return ( ! valid_unicode( hexdec( $hexchars ) ) ) ? "&amp;#x$hexchars;" : '&#x' . ltrim( $hexchars, '0' ) . ';';
}