The result is a String, which is the text {string} converted from encoding {from} to encoding {to}. When the conversion completely fails an empty string is returned. When some characters could not be converted they are replaced with "?". The encoding names are whatever the iconv() library function can accept, see ":!man 3 iconv". Most conversions require Vim to be compiled with the +iconv feature. Otherwise only UTF-8 to latin1 conversion and back can be done. This can be used to display messages with special characters, no matter what 'encoding' is set to. Write the message in UTF-8 and use:

echo iconv(utf8_str, "utf-8", &enc)

Note that Vim uses UTF-8 for all Unicode encodings, conversion from/to UCS-2 is automatically changed to use UTF-8. You cannot use UCS-2 in a string anyway, because of the NUL bytes.

Can also be used as a method:

GetText()->iconv('latin1', 'utf-8')