convert method
Converts string to its UTF-8 code units (a list of
unsigned 8-bit integers).
If start and end are provided, only the substring
string.substring(start, end) is converted.
Any unpaired surrogate character (U+D800-U+DFFF) in the input string
is encoded as a Unicode Replacement character U+FFFD (�).
Implementation
@override
Uint8List convert(String string, [int start = 0, int? end]) => utf8Encoder.convert(string, start, end);