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wp_kses_bad_protocol_once2() WP 1.0.0

Callback for wp_kses_bad_protocol_once() regular expression.

This function processes URL protocols, checks to see if they're in the whitelist or not, and returns different data depending on the answer.

No Hooks.

Return

String. Sanitized content.

Usage

wp_kses_bad_protocol_once2( $string, $allowed_protocols );
$string(string) (required)
URI scheme to check against the whitelist.
$allowed_protocols(string[]) (required)
Array of allowed URL protocols.

Code of wp kses bad protocol once2: wp-includes/kses.php WP 5.2.1

<?php
function wp_kses_bad_protocol_once2( $string, $allowed_protocols ) {
	$string2 = wp_kses_decode_entities( $string );
	$string2 = preg_replace( '/\s/', '', $string2 );
	$string2 = wp_kses_no_null( $string2 );
	$string2 = strtolower( $string2 );

	$allowed = false;
	foreach ( (array) $allowed_protocols as $one_protocol ) {
		if ( strtolower( $one_protocol ) == $string2 ) {
			$allowed = true;
			break;
		}
	}

	if ( $allowed ) {
		return "$string2:";
	} else {
		return '';
	}
}