How to extract the last byte out of an IP adress Newbie question:

I need to pass the last byte of a local IP as a parameter.
Eg.: when Ethernet.localIP() returns 192.168.0.100,
I need to extract the 100 and put it in a char array or string.

Anyone any ideas? Thx!
localIP() returns an IPAddress object.  That object has an operator for [] allowing you to access the individual parts of it.

IPAddress ip = Ethernet.localIP();
Serial.println(ip[3]);