toIso8601TimeString method
Returns an ISO-8601 full-precision extended format representation.
The format is HH:mm:ss.mmmuuuZ for UTC time, and
HH:mm:ss.mmmuuu (no trailing "Z") for local/non-UTC time,
where:
HHare hours in the range 00 to 23,mmare minutes in the range 00 to 59,ssare seconds in the range 00 to 59 (no leap seconds),mmmare milliseconds in the range 000 to 999, anduuuare microseconds in the range 001 to 999. If microsecond equals 0, then this part is omitted.
Implementation
String toIso8601TimeString() => toIso8601String().split("T").last;