c# - blocking timer in windows service -

i using 'timer code' in windows service:

var autoevent = new autoresetevent(false); timer = new timer(dowork, autoevent, 0, timeinmilliseconds); 

i wondering whether possible prevent invocation of dowork, if dowork has not finished yet? in other words, if timeinmilliseconds shorter time takes execute dowork?

if understand correctly can prevent automatic callback , change timer once when need.

timer = new timer(dowork, autoevent, 0, timeout.infinite);//prevent periodic timer  void dowork(object state) {     //do work , set timer again     timer.change(timeinmilliseconds, timeout.infinite); } 

don't forget add try/finally block, if don't timer not called again in case of exception.