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How to delay a timer from running or start it based on current date time

I have console application am using as demo to an App, it prints "hello", based on the timespan its expected to alert the user. when its not yet the timespan, i want to delay the app from printing hello and resume when its time.
public static async void timeCounter(int delae)
{
//This is suppose to cause a delay but it instead initiate the
//TimerOperation_Tick method.
await Task.Delay(delae);
// timer countdown
System.Timers.Timer timer = new System.Timers.Timer();
timer.Interval = 1000; // 1 second
timer.Elapsed += new ElapsedEventHandler(TimerOperation_Tick);
timer.Start();
if (obj.SubmissionCheck == true)
{
timer.Stop();
}
}
/// the event subscriber
private static void TimerOperation_Tick(object e, ElapsedEventArgs args)
{
if (timeFrame != 0)
{
Console.WriteLine("hi" + timeFrame);
timeFrame --;
if (timeFrame < 1)
{
obj.SubmissionCheck = true;
nt.Remove(obj);
startNotification();
}
}
}

Try setting timer.Enabled = false; This will prevent the timer ticks from occurring.

Timer does not fire in a multi-thread form

I have a System.Timers.Timer timer in a form. Also I have a thread that reads from an RFID device (with function: GetData()). I want to limit the time of my thread with a timer, but the timer does not fire.
System.Threading.Thread GetData;
System.Timers.Timer timer = new System.Timers.Timer();
int reverseCounter=1000;
public CardDragMaifareFrm()
{
timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
timer.Interval = 10;
timer.Enabled = true;
timer.Start();
GetData = new Thread(new ThreadStart(ReadCardData));
GetData.Start();
}
void timer_Elapsed(object sender, EventArgs e)
{
if (reverseCounter > 0)
{
MessageBox.Show("hey");
reverseCounter -= 1;
}
else
{// some actions for terminating GetData thread}
}
but I don't see "hey" message... can anybody help me? thanx

I used the first rule of computer engineering: Restart it, maybe it will work"... ;-)

Avoid multiple invoking of windows service using timer [duplicate]

I'm using a System.Timers.Timer in my application. Every second I run a function which does some job. The thing is, this function can block for some little time (it reads then processes a large file from disk). I want to start that function only if its previous "execution instance" has completed. I thought I could achieve this with a Mutex:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Timers;
using System.Threading;
namespace ConsoleApplication1
{
class Program
{
static Mutex TimerMut = new Mutex(false);
public static void Main()
{
Thread TT = new Thread(new ThreadStart(delegate()
{
System.Timers.Timer oTimer = new System.Timers.Timer();
oTimer.Elapsed += new ElapsedEventHandler(Handler);
oTimer.Interval = 1000;
oTimer.Enabled = true;
}));
TT.Start();
Console.Read();
}
private static void Handler(object oSource,
ElapsedEventArgs oElapsedEventArgs)
{
TimerMut.WaitOne();
Console.WriteLine("foo");
Thread.Sleep(500); //simulate some work
Console.WriteLine("bar");
TimerMut.ReleaseMutex();
}
}
}
That doesn't work, "foos" still appear every second. How can I achieve this?
EDIT: You're right, it makes no sense to start a new thread to handle this. I thought only System.Threading.Timer is launched in a separate thread.

I'm not sure why you are using a new thread to start the timer, since timers run on their own thread, but here's a method that works. Simply turn the timer off until you are done with the current interval.
static System.Timers.Timer oTimer
public static void Main()
{
oTimer = new System.Timers.Timer();
oTimer.Elapsed += new ElapsedEventHandler(Handler);
oTimer.Interval = 1000;
oTimer.Enabled = true;
}
private void Handler(object oSource, ElapsedEventArgs oElapsedEventArgs)
{
oTimer.Enabled = false;
Console.WriteLine("foo");
Thread.Sleep(5000); //simulate some work
Console.WriteLine("bar");
oTimer.Enabled = true;
}

If you want to skip the tick if another is already working you can do this.
private readonly object padlock = new object();
private void SomeMethod()
{
if(!Monitor.TryEnter(padlock))
return;
try
{
//Do heavy work
}
finally
{
Monitor.Exit(padlock);
}
}

Easiest way I know of to do this kind of thing:
internal static volatile bool isRunning;
public static void Main()
{
Thread TT = new Thread(new ThreadStart(delegate()
{
System.Timers.Timer oTimer = new System.Timers.Timer();
oTimer.Elapsed += new ElapsedEventHandler(Handler);
oTimer.Interval = 1000;
oTimer.Enabled = true;
}));
TT.Start();
}
private void Handler(object oSource,
ElapsedEventArgs oElapsedEventArgs)
{
if(isRunning) return;
isRunning = true;
try
{
Console.WriteLine("foo");
Thread.Sleep(500); //simulate some work
Console.WriteLine("bar");
}
finally { isRunning = false; }
}
The handler still runs, but the very first thing it does is make sure that another handler isn't running, and if one is, it stops immediately.
For timers executing handlers more quickly (like 3-4 times a second), this has the possibility to race; two threads could proceed past the guard clause before one of them sets the bit. You can avoid this with a couple of lock statements, similar to a Mutex or Monitor:
static object syncObj = new object();
private void Handler(object oSource,
ElapsedEventArgs oElapsedEventArgs)
{
lock(syncObj)
{
if(isRunning) return;
isRunning = true;
}
try
{
Console.WriteLine("foo");
Thread.Sleep(500); //simulate some work
Console.WriteLine("bar");
}
finally { lock(syncObj) { isRunning = false; } }
}
This will ensure that only one thread can ever be examining or modifying isRunning, and as isRunning is marked volatile, the CLR won't cache its value as part of each thread's state for performance; each thread has to look at exactly the same memory location to examine or change the value.

You can follow the following pattern to skip doing the indicated work if another invocation of this method is still running:
private int isWorking = 0;
public void Foo()
{
if (Interlocked.Exchange(ref isWorking, 1) == 0)
{
try
{
//Do work
}
finally
{
Interlocked.Exchange(ref isWorking, 0);
}
}
}
The approach that you were using with a Mutex will result in addition ticks waiting for earlier ticks to finish, not skipping invocations when another is still running, which is what you said you wanted. (When dealing with timers like this its common to want to skip such ticks, not wait. If your tick handlers regularly take too long you end up with a giant queue of waiting handlers.)

System.Timers.Timer() Firing multiple times due to aggregation of Elapsed Events

I want to have a section of my code start a timer once it's called, and I want this timer to keep running until I quit the whole program. My problem is, each time I call OnSomethingHappens() , the Elapsed events aggregate (despite my effort with -= ) and the timer starts firing one extra time (or at least this is what I think is happening). I have also tried defining the timer within the class, to no avail. Here's the related part of my code:
public override void OnSomethingHappens()
{
Timer aTimer= new System.Timers.Timer();
aTimer.Elapsed -= (sender, e) => DoSomethingElse(sender, e);
aTimer.Stop();
aTimer.Close();
aTimer.Elapsed += (sender, e) => DoSomethingElse(sender, e);
aTimer.Interval = 1000;
aTimer.AutoReset = true; // I want the timer to keep working, but only fire once each time
Console.WriteLine("Enabling Timer aTimer");
aTimer.Start();
}
I cannot use static (not sure how that would help but I saw timers being defined as static in many sources) because this class has many instances, and I want them to have separate timers.
Thank you.

Start your timer without the AutoReset and restart it at the end of the DoSomethingElse.
aTimer.AutoReset = false;
aTimer.Start();
DoSomethingElse(..)
{
// do stuff here
aTimer.Start();
}

if each instance of this class uses his own timer , so static is no needed.
private Timer _aTimer;
public void OnSomethingHappens()
{
if (_aTimer != null)
{
_aTimer.Enabled = true; // start timer
return;
}
_aTimer = new System.Timers.Timer();
_aTimer.Elapsed += DoSomethingElse;
_aTimer.Interval = 1000; // every 1 second
_aTimer.Enabled = true; // start timer
}
private void DoSomethingElse(object sender, ElapsedEventArgs e)
{
_aTimer.Enabled = false; // stop timer
// do w/e you want
}

First thing you should really only create once instance of the timer, and hook up one event listener. With your current code, a new timer is being created, with an event listener, every time the method is called. Instead make the timer a class variable, and hook up the event listener in the constructor.
You can start the timer in the OnSomethingHappens, but what do you want to happen on subsequent calls to the method? Should the timer restart, or just continue?
You would probably also want to make the class IDisposable, or at least provide a Stop method to stop the timer when the application closes.
public class MyClass : MyBaseClass, IDisposable
{
private Timer _timer;
private volatile bool _isStopped = true;
public MyClass()
{
_timer = new Timer();
_timer.Interval = 1000;
_timer.Elapsed = OnTimerElapsed;
}
public void Stop()
{
_isStopped = true;
_timer.Stop();
}
public void Dispose()
{
if (_timer != null)
{
Stop();
_timer = null;
}
}
protected override void OnSomethingHappens()
{
if (_timer.Enabled)
{
// Restart or do nothing if timer is already running?
}
else
{
_isStopped = false;
_timer.Start();
}
}
private void OnTimerElapsed(object sender, EventArgs a)
{
if (_isStopped)
{
// If the Stop method was called after the Elapsed event was raised, don't start a long running operation
return;
}
}
}

System.Timers.Timer Elapsed event executing after timer.Stop() is called

Background: I have a timer that I am using to keep track of how long it has been since the serialPort DataReceived event has been fired. I am creating my own solution to this instead of using the built in timeout event because I am getting a continuous stream of data, instead of sending a query and getting one response.
The Problem:
In the DataReceived handler I have a statement to stop the timer so that is doesn't elapse. the problem is that a lot of the time it still executes the Elapsed handler afterword.
I have read that is is possible to use SynchronizingObject to solve this problem but I am not sure how to accomplish that.
Here is my code: I tried to cut out everything that I didn't think was relevant.
private System.Timers.Timer timeOut;
private System.Timers.Timer updateTimer;
public void start()
{
thread1 = new Thread(() => record());
thread1.Start();
}
public void requestStop()
{
this.stop = true;
this.WaitEventTest.Set();
}
private void record()
{
timeOut = new System.Timers.Timer(500); //** .5 Sec
updateTimer = new System.Timers.Timer(500); //** .5 Sec
timeOut.Elapsed += TimeOut_Elapsed;
updateTimer.Elapsed += updateTimer_Elapsed;
updateTimer.AutoReset = true;
comport.Open();
comport.DiscardInBuffer();
comport.Write(COMMAND_CONTINUOUSMODE + "\r");
stopwatch.Reset();
stopwatch.Start();
recordingStartTrigger(); //** Fire Recording Started Event
timeOut.Start();
updateTimer.Start();
this.waitHandleTest.WaitOne(); //** wait for test to end
timeOut.Stop();
updateTimer.Stop();
comport.Write(COMMAND_COMMANDMODE + Environment.NewLine);
comport.DiscardInBuffer();
comport.Close();
recordingStopTrigger(status); //** Fire Recording Stopped Event
stopwatch.Stop();
}
//***********************************************************************************
//** Events Handlers
private void comDataReceived_Handler(object sender, SerialDataReceivedEventArgs e)
{
double force = -100000;
string temp = "-100000";
//timeOut.SynchronizingObject.Invoke(new Action(()=> {timeOut.Stop();}), new object[] {sender, e});
timeOut.Stop();
//** I removed my action code here, keep things simple.
timeOut.Start();
}
private void TimeOut_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
timeOut.Stop();
updateTimer.Stop();
//** fire delegate that GUI will be listening to, to update graph.
if (eventComTimeOut != null && this.stop == false)
{
if (eventComTimeOut(this, new eventArgsComTimeOut(comport.PortName, "READ")))
{
//retry = true;
comport.Write(COMMAND_CONTINUOUSMODE + "\r");
updateTimer.Start();
timeOut.Start();
}
else
{
this.stop = true;
//retry = false;
this.WaitEventTest.Set();
status = eventArgsStopped.Status.failed;
}
}
}
void updateTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
//** fire delegate that GUI will be listening to, to update graph.
List<Reading> temp = new List<Reading>(report.Readings_Force);
eventNewData(this, new eventArgsNewData(temp));
}

This is well known behavior. System.Timers.Timer internally uses ThreadPool for execution. Runtime will queue the Timer in threadpool. It would have already queued before you have called Stop method. It will fire at the elapsed time.
To avoid this happening set Timer.AutoReset to false and start the timer back in the elapsed handler if you need one. Setting AutoReset false makes timer to fire only once, so in order to get timer fired on interval manually start timer again.
yourTimer.AutoReset = false;
private void Timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
try
{
// add your logic here
}
finally
{
yourTimer.Enabled = true;// or yourTimer.Start();
}
}

I did a pause in timer with this code. for me that works.
Private cTimer As New System.Timers.Timer
Private Sub inittimer()
cTimer.AutoReset = True
cTimer.Interval = 1000
AddHandler cTimer.Elapsed, AddressOf cTimerTick
cTimer.Enabled = True
End Sub
Private Sub cTimerTick()
If cTimer.AutoReset = True Then
'do your code if not paused by autoreset false
End If
End Sub

Had the same problem and after some trying ended up with timer object to null and replace the timer variable it with a new timer object fixed the issue. I know its heavy of resources. But it solves the problem.