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How to ignore first Interval on first run of System.Windows.Form.Timer?

I have a timer that repeats at 1 second intervals. Users can Start() or Stop() the timer.
System.Windows.Form.Timer timer = new();
timer.Interval = 1000;
timer.Tick += (sender, e) =>
{
// Perform the action...
}
The problem is that in case of timer.Stop() it reacts immediately after pressing, but in case of timer.Start() it works after 1 second. This may feel strange to users.
So I solved it like this:
System.Windows.Form.Timer timer = new();
timer.Interval = 1;
timer.Tick += (sender, e) =>
{
if (timer.Interval == 1)
{
timer.Interval = 1000;
}
// Perform the action...
}
private void StopButton_Click(object sender, EventArgs e)
{
timer.Stop();
timer.Interval = 1;
}
However, there is a problem that the timer's Interval must be continuously set to 1. One timer is fine, but having multiple complicates things.
Is there any other way?

Following comments from #jmcilhinney and #Zohar Peled, I solved it like this:
System.Windows.Form.Timer timer = new();
timer.Interval = 1000;
timer.Tick += (sender, e) =>
{
StartOnFirstTimer();
}
private void StartOnFirstTimer()
{
// Perform the action...
}
private void StartButton_Click(object sender, EventArgs e)
{
StartOnFirstTimer();
timer.Start();
}
It is extracted the part corresponding to the timer's Tick event into a method and call it before starting it.

C# - Win Form stopping Timer tick

This is my implementation of a Win Form app that has a countdown timer:
readonly DateTime myThreshold;
public Form1()
{
InitializeComponent();
myThreshold = Utils.GetDate();
Timer timer = new Timer();
timer.Interval = 1000; //1 second
timer.Tick += new EventHandler(t_Tick);
timer.Start();
//Threshold check - this only fires once insted of each second
if (DateTime.Now.CompareTo(myThreshold) > 0)
{
// STOP THE TIMER
timer.Stop();
}
else
{
//do other stuff
}
}
void t_Tick(object sender, EventArgs e)
{
TimeSpan timeSpan = myThreshold.Subtract(DateTime.Now);
this.labelTimer.Text = timeSpan.ToString("d' Countdown - 'hh':'mm':'ss''");
}
The wanted behavior is to stop the timer and the tick function when the threshold is reached.
This now does not happens because the check is only executed once since it is placed in the Form1 initialization.
Does exist a way to add this check in a way to immediately stop the Timer once a condition has been meet?

If we define timer as a class field (so it can be accessed from all methods in the class), then we can just add the check to the Tick event itself, and stop the timer from there:
private Timer timer = new Timer();
void t_Tick(object sender, EventArgs e)
{
// Stop the timer if we've reached the threshold
if (DateTime.Now > myThreshold) timer.Stop();
TimeSpan timeSpan = myThreshold.Subtract(DateTime.Now);
this.labelTimer.Text = timeSpan.ToString("d' Countdown - 'hh':'mm':'ss''");
}

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;
}
}
}

Timer won't tick

I have a Windows.Forms.Timer in my code, that I am executing 3 times. However, the timer isn't calling the tick function at all.
private int count = 3;
private timer;
void Loopy(int times)
{
count = times;
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
void timer_Tick(object sender, EventArgs e)
{
count--;
if (count == 0) timer.Stop();
else
{
// Do something here
}
}
Loopy() is being called from other places in the code.

Try using System.Timers instead of Windows.Forms.Timer
void Loopy(int times)
{
count = times;
timer = new Timer(1000);
timer.Enabled = true;
timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
timer.Start();
}
void timer_Elapsed(object sender, ElapsedEventArgs e)
{
throw new NotImplementedException();
}

If the method Loopy() is called in a thread that is not the main UI thread, then the timer won't tick.
If you want to call this method from anywhere in the code then you need to check the InvokeRequired property. So your code should look like (assuming that the code is in a form):
private void Loopy(int times)
{
if (this.InvokeRequired)
{
this.Invoke((MethodInvoker)delegate
{
Loopy(times);
});
}
else
{
count = times;
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
}

I am not sure what you are doing wrong it looks correct, This code works: See how it compares to yours.
public partial class Form1 : Form
{
private int count = 3;
private Timer timer;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
Loopy(count);
}
void Loopy(int times)
{
count = times;
timer = new Timer();
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
void timer_Tick(object sender, EventArgs e)
{
count--;
if (count == 0) timer.Stop();
else
{
//
}
}
}

Here's an Rx ticker that works:
Observable.Interval(TimeSpan.FromSeconds(1))
.Take(3)
.Subscribe(x=>Console.WriteLine("tick"));
Of course, you can subscribe something more useful in your program.

you may have started the timer from another thread, so try invoking it from the correct thread.
for example, instead of:
timerX.start();
Use:
Invoke((MethodInvoker)delegate { timerX.Start(); });

Check if your timer in properties is enabled.
Mine was false and after setting to true it worked.

If you are using Windows.Forms.Timer then should use something like following.
//Declare Timer
private Timer _timer= new Timer();
void Loopy(int _time)
{
_timer.Interval = _time;
_timer.Enabled = true;
_timer.Tick += new EventHandler(timer_Elapsed);
_timer.Start();
}
void timer_Elapsed(object sender, EventArgs e)
{
//Do your stuffs here
}

If you use some delays smaller than the interval inside the timer, the system.timer will execute other thread and you have to deal with a double thread running at the same time. Apply an InvokeRequired to control the flow.

system windows forms timer parameters

How can you pass the parameter to a System.Windows.Forms.Timer?
private System.Windows.Forms.Timer timer;
timer.Interval = 1000;
timer.Tick += new EventHandler(timer_Tick);
timer.start
private void timer_Tick(object sender, EventArgs e)
{
}
How can I pass the value of the object sender?

Simple timer code - there is no need to pass any sender its get call when interval time ends.
Timer t = new Timer();
t.Interval = 2000;
timer1.Enabled = true;
timer1.Tick += new System.EventHandler(OnTimerEvent);
//You can use Tag property of your timer as userState
void timer1_Tick(object sender, EventArgs e)
{
Timer timer = (Timer)sender;
MyState state = timer.Tag as MyState;
int x = state.Value;
}
have look to this for detail : http://www.c-sharpcorner.com/UploadFile/mahesh/WorkingwithTimerControlinCSharp11302005054911AM/WorkingwithTimerControlinCSharp.aspx

I guess there is a Tag property on timer class.