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''");
}
Related
I'm implementing a countdown in my app
private async void Window_Activated(object sender, WindowActivatedEventArgs args)
{
dispatcherTimer = new DispatcherTimer();
dispatcherTimer.Tick += dispatcherTimer_Tick;
dispatcherTimer.Interval = new TimeSpan(0,1,0);
dispatcherTimer.Start();
}
private void dispatcherTimer_Tick(object sender, object e)
{
TimeSpan timeSpan = new TimeSpan(blockTime.Hours, blockTime.Minutes, blockTime.Seconds);
if (timeSpan != TimeSpan.Zero)
{
timeSpan = timeSpan.Subtract(TimeSpan.FromMinutes(1));
Countdown_TexBlock.Text = String.Format("{0}:{1}", timeSpan.Hours, timeSpan.Minutes);
dispatcherTimer.Start();
}
else
{
dispatcherTimer.Stop();
}
}
The code works but only one time
For example I put 15 minutes in the blocktime (the time that the countdown will be running)
after a minute the countdown.text would be 0:14.
So only works after the first minute
Is not supposed to be restarted with dispatcher.start()
In the code that you posted, I don't see the blockTime variable being changed to any other value than it has in the beginning. This means that on every tick of dispatchTimer the value of the timeSpan.Subtract expression will always evaluate to the same 14 minutes. In your code, that 14 minutes is assigned to a local vaiable that is disposed when the tick is over. This gives the appearance that the dispatchTimer has stopped issuing Tick when it hasn't.
Here's what I ran that works as expected (for testing, I changed the minutes to seconds to make it observable in a reasonable time).
public sealed partial class MainWindow : Window
{
public MainWindow()
{
this.InitializeComponent();
// Create the dispatch timer ONCE
dispatcherTimer = new DispatcherTimer();
dispatcherTimer.Tick += DispatcherTimer_Tick;
dispatcherTimer.Interval = TimeSpan.FromSeconds(1);
// This will restart the timer every
// time the window is activated
this.Activated += (sender, e) =>
{
startOrRestartDispatchTimer();
};
}
private void startOrRestartDispatchTimer()
{
dispatcherTimer.Stop(); // If already running
blockTime = TimeSpan.FromSeconds(15);
Countdown_TexBlock.Text = blockTime.ToString();
dispatcherTimer.Start();
}
private void DispatcherTimer_Tick(object sender, object e)
{
if (blockTime > TimeSpan.Zero)
{
blockTime = blockTime.Subtract(TimeSpan.FromSeconds(1));
Countdown_TexBlock.Text = blockTime.ToString();
if (blockTime == TimeSpan.Zero)
{
Countdown_TexBlock.Text = "Done";
dispatcherTimer.Stop();
}
}
}
TimeSpan blockTime = TimeSpan.FromSeconds(15);
private DispatcherTimer dispatcherTimer;
// This will restart the timer when the button is clicked.
private void buttonRestart_Click(object sender, RoutedEventArgs e) =>
startOrRestartDispatchTimer();
}
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"... ;-)
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;
}
}
}
I am developing a C# desktop application. I want my all open windows to pop up (something which happens with Alt + Tab) every 5th minute. I looked at a few questions here. They suggest doing it by using timers, but how do I pop up the minimised windows?
Here is a really basic example for you to work on.
First create the timer.
Create a function that will run when the timer ticks.
Then add an event to run every time it ticks. And link it your function
Inside that function check if it has been 5 minutes. If so, maximize
the window
public partial class TimerForm : Form
{
Timer timer = new Timer();
Label label = new Label();
public TimerForm ()
{
InitializeComponent();
timer.Tick += new EventHandler(timer_Tick); // Everytime timer ticks, timer_Tick will be called
timer.Interval = (1000) * (1); // Timer will tick evert second
timer.Enabled = true; // Enable the timer
timer.Start(); // Start the timer
}
void timer_Tick(object sender, EventArgs e)
{
// HERE you check if five minutes have passed or whatever you like!
// Then you do this on your window.
this.WindowState = FormWindowState.Maximized;
}
}
Here is the complete solution
public partial class Form1 : Form
{
int formCount = 0;
int X = 10;
System.Windows.Forms.Timer timer = new System.Windows.Forms.Timer();
public Form1()
{
InitializeComponent();
timer.Tick += new EventHandler(timer_Tick); // Everytime timer ticks, timer_Tick will be called
timer.Interval = (1000) * X; // Timer will tick evert second
timer.Enabled = true; // Enable the timer
timer.Start();
}
void timer_Tick(object sender, EventArgs e)
{
FormCollection fc = new FormCollection();
fc = Application.OpenForms;
foreach (Form Z in fc)
{
X = X + 5;
formCount++;
if (formCount == fc.Count)
X = 5;
Z.TopMost = true;
Z.WindowState = FormWindowState.Normal;
System.Threading.Thread.Sleep(5000);
}
}
}
My program has a parameter that starts up the winform and waits x number of seconds before it runs a function. Currently I am using Thread Sleep for x seconds and then the function runs. how can I add a timer in the strip status label?
so that it says: x Seconds Remaining...
Instead of blocking thread execution, simply call your method when required timeout passes. Place new Timer to your form, and set it's Interval to 1000. Then subscribe to timer's Tick event and calculate elapsed time in event handler:
private int secondsToWait = 42;
private DateTime startTime;
private void button_Click(object sender, EventArgs e)
{
timer.Start(); // start timer (you can do it on form load, if you need)
startTime = DateTime.Now; // and remember start time
}
private void timer_Tick(object sender, EventArgs e)
{
int elapsedSeconds = (int)(DateTime.Now - startTime).TotalSeconds;
int remainingSeconds = secondsToWait - elapsedSeconds;
if (remainingSeconds <= 0)
{
// run your function
timer.Stop();
}
toolStripStatusLabel.Text =
String.Format("{0} seconds remaining...", remainingSeconds);
}
You can use a Timer:
public class Form1 : Form {
public Form1(){
InitializeComponent();
t = new Timer {Interval = 1000};
t.Tick += Tick;
//try counting down the time
CountDown(100);
}
DateTime start;
Timer t;
long s;
public void CountDown(long seconds){
start = DateTime.Now;
s = seconds;
t.Start();
}
private void Tick(object sender, EventArgs e){
long remainingSeconds = s - (DateTime.Now - start).TotalSeconds;
if(remainingSeconds <= 0) {
t.Stop();
toolStripStatusLabel1.Text = "Done!";
return;
}
toolStripStatusLabel1.Text = string.Format("{0} seconds remaining...", remainingSeconds);
}
}