= 0x00 && $codePoint <= 0x7F ) { return chr( $codePoint ); } $count = 0; $offset = 0; if ( $codePoint >= 0x0080 && $codePoint <= 0x07FF ) { $count = 1; $offset = 0xC0; } elseif ( $codePoint >= 0x0800 && $codePoint <= 0xFFFF ) { $count = 2; $offset = 0xE0; } elseif ( $codePoint >= 0x10000 && $codePoint <= 0x10FFFF ) { $count = 3; $offset = 0xF0; } $bytes = chr( ( $codePoint >> ( 6 * $count ) ) + $offset ); while ( $count > 0 ) { $temp = $codePoint >> ( 6 * ( $count - 1 ) ); $bytes .= chr( 0x80 | ( $temp & 0x3F ) ); -- $count; } return $bytes; } /** * Takes a UTF-8 encoded string and converts it into a series of integer code points. Any * invalid byte sequences will be replaced by a U+FFFD replacement code point. * * @see https://encoding.spec.whatwg.org/#utf-8-decoder * * @return list */ public static function utf8Decode( string $input ): array { $bytesSeen = 0; $bytesNeeded = 0; $lowerBoundary = 0x80; $upperBoundary = 0xBF; $codePoint = 0; $codePoints = []; $length = strlen( $input ); for ( $i = 0; $i < $length; ++ $i ) { $byte = ord( $input[ $i ] ); if ( $bytesNeeded === 0 ) { if ( $byte >= 0x00 && $byte <= 0x7F ) { $codePoints[] = $byte; continue; } if ( $byte >= 0xC2 && $byte <= 0xDF ) { $bytesNeeded = 1; $codePoint = $byte & 0x1F; } elseif ( $byte >= 0xE0 && $byte <= 0xEF ) { if ( $byte === 0xE0 ) { $lowerBoundary = 0xA0; } elseif ( $byte === 0xED ) { $upperBoundary = 0x9F; } $bytesNeeded = 2; $codePoint = $byte & 0xF; } elseif ( $byte >= 0xF0 && $byte <= 0xF4 ) { if ( $byte === 0xF0 ) { $lowerBoundary = 0x90; } elseif ( $byte === 0xF4 ) { $upperBoundary = 0x8F; } $bytesNeeded = 3; $codePoint = $byte & 0x7; } else { $codePoints[] = 0xFFFD; } continue; } if ( $byte < $lowerBoundary || $byte > $upperBoundary ) { $codePoint = 0; $bytesNeeded = 0; $bytesSeen = 0; $lowerBoundary = 0x80; $upperBoundary = 0xBF; -- $i; $codePoints[] = 0xFFFD; continue; } $lowerBoundary = 0x80; $upperBoundary = 0xBF; $codePoint = ( $codePoint << 6 ) | ( $byte & 0x3F ); if ( ++ $bytesSeen !== $bytesNeeded ) { continue; } $codePoints[] = $codePoint; $codePoint = 0; $bytesNeeded = 0; $bytesSeen = 0; } // String unexpectedly ended, so append a U+FFFD code point. if ( $bytesNeeded !== 0 ) { $codePoints[] = 0xFFFD; } return $codePoints; } }