/**
* Encode the Unicode values to be used in the URI.
*
* @since 1.5.0
*
* @param string $utf8_string
* @param int $length Max length of the string
* @return string String with Unicode encoded for URI.
*/
function utf8_uri_encode( $utf8_string, $length = 0 ) {
$unicode = '';
$values = array();
$num_octets = 1;
$unicode_length = 0;
$string_length = strlen( $utf8_string );
for ($i = 0; $i < $string_length; $i++ ) {
$value = ord( $utf8_string[ $i ] );
if ( $value < 128 ) {
if ( $length && ( $unicode_length >= $length ) )
break;
$unicode .= chr($value);
$unicode_length++;
} else {
if ( count( $values ) == 0 ) $num_octets = ( $value < 224 ) ? 2 : 3;
$values[] = $value;
if ( $length && ( $unicode_length + ($num_octets * 3) ) > $length )
break;
if ( count( $values ) == $num_octets ) {
if ($num_octets == 3) {
$unicode .= '%' . dechex($values[0]) . '%' . dechex($values[1]) . '%' . dechex($values[2]);
$unicode_length += 9;
} else {
$unicode .= '%' . dechex($values[0]) . '%' . dechex($values[1]);
$unicode_length += 6;
}
$values = array();
$num_octets = 1;
}
}
}
return $unicode;
}