1.创建定时器
//创建Timer
self.timer=dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER,0,0,dispatch_get_main_queue());
//设置定时器的触发时间（1秒后）和时间间隔（每隔2秒）
dispatch_source_set_timer(self.timer,dispatch_time(DISPATCH_TIME_NOW,1*NSEC_PER_SEC),2*NSEC_PER_SEC,0);
//设置回调
dispatch_source_set_event_handler(self.timer, ^{
NSLog(@"Timer %@", [NSThreadcurrentThread]);
});
//开始定时器
dispatch_resume(self.timer);
2.取消定时器
dispatch_cancel(self.timer);
self.timer=nil;
注意：GCD定时器不用加入RunLoop
Dome:
