port property
The port that the server is listening on.
This is the actual port used when a port of zero is specified in the bind or bindSecure call.
Implementation
int get port;© 2012 the Dart project authors
Licensed under the BSD 3-Clause "New" or "Revised" License.
https://api.dart.dev/stable/2.18.5/dart-io/HttpServer/port.html