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Use a Timer to increment a ProgressBar and show a count-down

I need some help in making a count-down Timer that also increments a ProgressBar.
I have a Button that generates a random time (expressed in minutes) that will increment a ProgressBar, to use as a form of loader.
When the ProgressBar increments its value, I would like to show, in a Label, the time remaining.
Here is my code:
int RandomNumber;
int MinutesElapsed;
private void button1_Click(object sender, EventArgs e)
{
Random random = new Random((int)DateTime.Now.Ticks);
RandomNumber = random.Next(1, 121); // at (x, x) there is a limit from x to x+1
MinutesElapsed = 0;
QuestTimer1.Start(); // starts the timer
}
private void QuestTimer1_Tick(object sender, EventArgs e)
{
MinutesElapsed++;
double minutes = MinutesElapsed / 1.2;
progressBar1.Value = (int)minutes;
}

This may seem counterintuitive, but when implementing a "timer," there is no need for an actual timer to keep the time. You certainly don't need to set a timer and increment a variable every second-- your system clock already does that! Your program just needs to know the start time, end time, and current time, and at any given moment, in can compute the progress % and the time remaining.
When you start the process, take note of the current time and store the target completion time.
DateTime _startTime;
DateTime _endTime;
private void StartTimer_Click(object sender, EventArgs e)
{
_startTime = DateTime.Now;
var duration = random.Next(1, 121);
_endTime = _startTime.AddSeconds(duration);
}
Then when you wish to know the time remaining or progress, compute them:
public int SecondsRemaining => (_endTime - DateTime.Now).TotalSeconds;
public double PercentComplete => ((double)(_endTime - DateTime.Now).TotalMilliseconds) / (_endTime - _startTime).TotalMilliseconds;
You can call either of these properties at any time and they will always give you the percent complete and time remaining accurately. You don't need a separate timer at all!
However, you probably want to update the display every now and then. You need a timer for that, but it can run at any interval, and it's easy to write:
void Timer_Tick(object sender, EventArgs e)
{
this.TimeRemainingLabel.Text = SecondsRemaining.ToString() + " seconds";
this.ProgressBar.Value = (int)(PercentComplete * 100);
}

A few notes that may be useful:
Your Button (you should give it a proper name) can be used to start/stop the Timer and generate a new random number, representing minutes, using a Random object (declared as a static Field - not so important here, but because of its internal functionality, it's more reliable this way).
The generated random value initializes a TimeSpan object (totalTime) that store the total time, to keep as reference.
You can set a measure of time directly in the TimeSpan constructor: if the values - expressed in minutes here - overflows the normal measure (60 minutes in this case), the TimeSpan class computes the correct value (i.e., if you set the Minutes component to 90 in the constructor, the TimeSpan will be automatically compute 1 Hour and 30 minutes).
Another TimeSpan (minutesElapsed) will store the time elapsed.
The Timer's Interval is set to 1000ms.
The ProgrssBar should keep its standard range of values: (0 - 100).
You can see it as the percentage of completion. Each time the Timer ticks, we'll adapt the difference between the total time and the elapsed time, squeezing it in this range of values .
TimeSpan totalTime;
TimeSpan minutesElapsed;
static Random rnd = new Random();
private void button1_Click(object sender, EventArgs e)
{
QuestTimer1.Stop();
minutesElapsed = new TimeSpan(0, 0, 0);
// 0 Hours, N Minutes, 0 Seconds
totalTime = new TimeSpan(0, rnd.Next(1, 121), 0);
lblTimeLeft.Text = totalTime.ToString(#"hh\:mm\:ss");
QuestTimer1.Start();
}
The Timer ticks - 1 second has passed - so increment the elapsed time by one second and calculate the difference between the total time and the current number of elapsed seconds.
TimeSpan objects support common operators to perform addition and subtraction and provide different properties to evaluate their value in Ticks, Milliseconds, Seconds etc.
Each second, a Label (here named lblTimeLeft) is updated, showing how many seconds are left (acts as a count-down), while the ProgressBar increments it's Value.
When minutesElapsed >= totalTime, the Timer is stopped.
private void QuestTimer1_Tick(object sender, EventArgs e)
{
minutesElapsed += TimeSpan.FromSeconds(1);
lblTimeLeft.Text = (totalTime - minutesElapsed).ToString(#"hh\:mm\:ss");
progressBar1.Value = (int)(minutesElapsed.TotalMinutes / totalTime.TotalMinutes * 100D);
if (minutesElapsed.TotalMinutes >= totalTime.TotalMinutes) {
QuestTimer1.Stop();
}
}

Reduce an integer every second in c# [closed]

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I'm trying to figure out how to reduce an integer every second. Everything suggests things that are many, many lines long, and are explaining things in a generic, interchangeable way. So far I've set it up as...
public int timer = 180;
public Text timerCounterText;
// Use this for initialization
void Start ()
{
timerCounterText.text = "Time Left: " + timer.ToString();
}
Now I have no idea how to actually make the integer decrease by one each second, I don't want any suggestions of a potentially better way to do it unless there's no way to do it from what I have here.
I just want a simple, in as few lines as possible way to reduce my timer integer by 1 each second, as the way I have done this is the only way I understand how to do this so far.
Sorry if this is too much to ask, I just want a script I can understand, not just one that works best, as I'm just a student, not making a product.

I have worked a lot with timers in C# (a HELL of a lot - I used to develop software for a Sports Timing company).
There are a few ways of doing it. Some more accurate than others.
The simplest - which is the way you're looking at would be like so:
Set your total seconds in a private field:
private int _secondsRemaining = 180; // 3 minutes
Create a Timer stored in a private field:
private System.Timers.Timer _countdownTimer;
Create a StartTimer() method. Initialize the _countdownTimer, and create an Event Handler for when the timer ticks - this is what happens when it "reaches 0"/fires/whatever you want to call it:
public void StartTimer()
{
_countdownTimer = new System.Timers.Timer(1000); // 1000 is the number of milliseconds
// 1000ms = 1 second
// Set a handler for when the timer "ticks"
// The "Tick" event will be fired after 1 second (as we've set it)
// The timer will loop, though and keep firing until we stop it
// Or unless it is set to not automatically restart
_countdownTimer.Tick += OnTimer_Tick;
// Start the timer!
_countdownTimer.Start();
}
You will need to call StartTimer() from somewhere in your program, otherwise it won't ever start (obviously) - you can do this from the constructor or a button click etc.
Now, create an Event Handler for when the timer ticks. In this, decrement (take 1 from) the _secondsRemaining value; and then display it in your timerCounterText label:
// This is what gets fired when the timer "reaches 0"
private void OnTimer_Tick(object sender, ElapsedEventArgs e)
{
_secondsRemaining--; // the same as "_secondsRemaining = secondsRemaining -1"
timerCounterText.Text = string.Format("Time Remaining: {0} seconds",
_secondsRemaining);
}
This is a nice and easy way to make a countdown timer.
The drawback is, that the timer doesn't fire EXACTLY every second, so you may notice a little bit of drift.
Like I mentioned; depending on the accuracy you need, there are other ways I have used. It depends on what the timer's being used for.
WAIT! There's more!
What would also be useful (if you need it), is, when the _secondsRemaining reaches 0 to stop the timer.
Create a StopTimer() method:
private void StopTimer()
{
if (_countdownTimer != null)
{
_countdownTimer.Tick -= OnTimer_Tick;
_countdownTimer.Stop();
_countdownTimer.Dispose();
_countdownTimer = null;
}
}
You could also use this method when you want to stop the timer manually from a button click or whatever.
Notice the null check, and the code within it. The null check is just for damage limitation in case the _countdownTimer hasn't been initialized etc. and to stop your program bombing out if so.
The code within the if check unsubscribes from the Tick event, stops the timer (obviously), and then gets rid of the _countdownTimer - you don't need to; but you will need to unsubscribe & stop it...
If we called StartTimer() again and initialized the timer, we'd be adding another subscription to the Tick event - this would cause the OnTimer_Tick method to be called twice every time the _countdownTimer fires (and so on and so forth).
Now, in your OnTimer_Tick handler, where we decrement the value of _secondsRemaining - check after, if it is less or equal to 0:
private void OnTimer_Tick(object sender, ElapsedEventArgs e)
{
_secondsRemaining--; // decrement the _secondsRemaining as before
if (_secondsRemaining <= 0)
{
StopTimer(); // This will stop the timer when the _secondsRemaining
// reach 0 (or go below - it shouldn't)
// You can also add in other stuff to happen at 0
// such as "Ending the game", as you described
}
// Display the time remaining, still - as before
timerCounterText.Text = string.Format("Time Remaining: {0} seconds",
_secondsRemaining);
}
Where the check for _secondsRemaining <= 0 is, you could also add your own methods for other things to happen - such as Ending your game as you asked in your question :)
I won't go into any more detail; and I'll let you figure it out - but you could even add in ResetTimer() methods, so you could start the timer again.
I hope this helps - any questions or any other ways to do timers you need; just ask.

I would advise a separate thread doing a decrease in the integer. I would do this with a while loop
public event SecondHappenedEventHandler SecondHappened;
public delegate void SecondHappenedEventHandler(int second);
private int timer = 180;
Public Void Start()
{
timer = 180;
Thread th = New Thread(New ThreadStart(Monitor);
th.Start();
}
Private Void Monitor()
{
While (timer != 0)
{
timer--;
SecondHappened(timer);
Thread.Sleep(1000); //This is milliseconds
}
}
My C# is a little rusty since I have been doing VB more recently for work. Then Add a raiseevent in that class that passes back the integer to the the other class. So your other class would make an instance of this class and have an event that gets the second passed back and display it to the end user.
public Text timerCounterText;
private TimerClass timer;
// Use this for initialization
void Start ()
{
timer.Start
}
private void SecondHappened(int timerBack)
{
timerCounterText.text = "Time Left: " + timerBack.ToString();
}

You can use one of the few Timer classes in .NET in order to get your program do stuff in regular intervals. There's usually one type of timer class that is appropriate for a given situation depending on your app type(i.e. Windows, Console, Service...etc)
Since you are after a simple example, you can have a look at the System.Timers.Timer class:
Generates an event after a set interval, with an option to generate recurring events.
Example of it's usage in a console application (P.S. If you have Windows Forms apps, you probably don't want to use it in this way):
int _countDown = 180;
void Start()
{
var timer = new System.Timers.Timer(1000); // Duration in milliseconds
timer.Elapsed += async ( sender, e ) => await HandleTimer();
timer.Start();
}
void HandleTimer()
{
_countDown--;
Console.WriteLine("Time Left: {0}", _countDown);
}

If you work in WF (Windows Forms), I suggest using a Timer. Create a timer control, set it's interval to 1000 (milliseconds), and in your start function just enable it:
void Start ()
{
timer1.Enabled = true;
timerCounterText.text = "Time Left: " + timer.ToString();
}
Now, a double click on the timer should create a timer_tick event. Use it like that:
void timer_Tick(object sender, EventArgs e)
{
timerCounterText.text = "Time Left: " + (--timer).ToString();
}
Then it should reduce the timer by 1 every second. Of course you should check when it arrives to 0, and then set timer1.Enabled to false.

Using the Decrement Operator --
If you wanted to decrement it prior to the value being updated, you could use the decrement operator --:
void Start ()
{
// This will decrement the timer by 1
timer--;
// Output the value
timerCounterText.Text = "Time Left: " + timer.ToString();
}
You could also accomplish this same thing inline using prefix notation, which will update the value prior to using it :
void Start ()
{
// Decrement your count and output it
timerCounterText.Text = "Time Left: " + (--timer).ToString();
}
Cleaning Up Your Output
You can clean up your output a bit more by using the String.Format() method as well :
void Start ()
{
// Decrement your count and output it
timerCounterText.Text = String.Format("Time Left: {0}",--timer);
}
or if you are using C#, you can take advantage of String Interpolation :
void Start ()
{
// Decrement your count and output it
timerCounterText.Text = $"Time Left: {--timer}";
}
Making Your Timer Tick
Assuming that you are using a Timer class, you can set it's Tick event to be triggered as a certain interval. This is what you would use to actually decrement your value and output it to the user :
// Define a timer
Timer countDown = new Timer();
// Sets the timer interval to 1 seconds.
countDown.Interval = 1000;
// Call the tick event every second
countDown.Tick += new EventHandler(Tick);
// Start your timer
countDown.Start();
and your Tick event would look like this :
private static void Tick(Object myObject,EventArgs myEventArgs)
{
// Check if your timer has run out
if(countDown <= 0)
{
// Timer has run out, handle accordingly
countDown.Stop();
}
else
{
// Otherwise output and decrement
String.Format("Time Left: {0}",--timer);
}
}

C#, System.Timers.Timer, run every 15min in sync with system clock

How do I get System.Timers.Timer to trigger Elapsed events every 15 mins in sync with the system clock? In other words, I want it to trigger exactly at xx:00, xx:15, xx:30, xx:45 (where xx means any hour)

You could let it elapse every second and check whether the current time is 00, 15, 30 or 45 and only then forward the event.
A first idea would be:
private static System.Timers.Timer aTimer;
private static System.DateTime _last;
public static void Main()
{
aTimer = new System.Timers.Timer(10000);
aTimer.Elapsed += new ElapsedEventHandler(OnTimedEvent);
aTimer.Interval = 1000;
aTimer.Enabled = true;
Console.WriteLine("Press the Enter key to exit the program.");
Console.ReadLine();
}
private static void OnTimedEvent(object source, ElapsedEventArgs e)
{
DateTime time =
new DateTime( 1,1,1, DateTime.Now.Hours, DateTime.Now.Minute );
if( time.Minute==0 ||time.Minute==15 || time.Minute==30 || time.Minute==45 )
{
// Avoid multiple notifications for the same quarter.
if ( _last==DateTime.MinValue || _last!=time )
{
_last = time;
// Do further processing.
doProcessing();
}
}
}
(Example based on this MSDN documentation)

When starting the program, or changing the event times that will be triggered, load the event times into memory (to keep from reading this data from the hard drive every second.) Then set up a timer to fire every 1 second. A timer set to fire every 1 second is very little overhead on the processor. Set one up and open task manager and you will not even notice the processor running any more than before the timer was running. Then put a check in the timer event to check if it is time to fire an event.

use Quartz.net. Then you can use regex to define the interval.

Exactly fire tick event on completion of hour in C# Timer

I want the tick event to fire every hour exactly on completion of the hour. For e.g. it should tick on 8 am then on 9 am then on 10 am etc.
It's simple that I need to set the Interval to 3600000.
The problem here is how should I identify when should I start the timer?
I'm creating a tool which will run in system tray from the time when user will log on.

Please don't create a program that does nothing but waste memory. That's what Windows' Task Scheduler is for. Run your program every hour from such a task.
http://msdn.microsoft.com/en-us/library/aa384006%28v=VS.85%29.aspx
Here's a sample:
Go to Start->Programs->Accessories->Scheduled Tasks.
On the right side, click "Add Task..".
Select your executable.
Go to the Trigger tab.
Create Trigger with the following selection:
.
Run Daily
Start today at 8:00 am
Repeat every 1 Hour
I'm sorry that I can't provide any screenshots since I'm running the german version of Windows 7.

Maybe the following code is buggy, but the idea is like this:
public void InitTimer()
{
DateTime time = DateTime.Now;
int second = time.Second;
int minute = time.Minute;
if (second != 0)
{
minute = minute > 0 ? minute-- : 59;
}
if (minute == 0 && second == 0)
{
// DoAction: in this function also set your timer interval to 3600000
}
else
{
TimeSpan span = new TimeSpan(0, 60 - minute, 60 - second);
timer.Interval = (int) span.TotalMilliseconds - 100;
timer.Tick += new EventHandler(timer_Tick);
timer.Start();
}
}
void timer_Tick(object sender, EventArgs e)
{
timer.Interval = 3600000;
// DoAction
}
Per #smirkingman's suggestion, I removed 100 millisecond because of latency of project start-up and running time of the application:
timer.Interval = (int) span.TotalMilliseconds - 100;

I think it could be easier if you set up a timer every, let's say, minute, and this timer can check the system clock, when the desired time is less or equal than system time you can just run the actions (in this example with an error of 1 minute maximun)
You can improve it if you make the timer interval dinamyc, for example if you check the time and is still half an hour left you can set the interval for 15 minutes, nex time you reduce it to 5 minutoes and so on until you are checking the clock once a second, for examlpe.
HTH

Here's how I did this. The Tick event fires every 20 seconds. Simply change the minutes == "xxx" to whatever time you want the event to fire. If you need events spread out over hours, simply make the interval timer longer. Simple and effective.
private void timer1_Tick(object sender, EventArgs e)
{
DateTime Time = DateTime.Now;
int minutes = Time.Minute;
if (minutes == 00) //FIRE ON THE HOUR
{ DO THIS }
if (minutes == 15) //FIRE ON 1/4 HOUR
{ DO THIS }
if (minutes == 30) //FIRE ON 1/2 HOUR
{ DO THIS }
if (minutes == 45) //FIRE ON 3/4 HOUR
{ DO THIS }
}

Instead of firing the timer once an hour, maybe it would be more appropriate to fire the timer once a minute, and check to see if it's time yet.
The only problem with this is the worst case lag is 59 seconds. If you need it to fire exactly on the hour (at 10 am sharp), you may need to do some fiddling with the interval the first time so you line up.

Execute an operation every x seconds for y minutes in c#

I need to run a function every 5 seconds for 10 minutes.
I use a timer to run it for 5 secs, but how do I limit the timer to only 10 mins?

Just capture the time that you want to stop and end your timer from within the elapsed handler. Here's an example (note: I used a System.Threading.Timer timer. Select the appropriate timer for what you are doing. For example, you might be after a System.Windows.Forms.Timer if you are writing in Winforms.)
public class MyClass
{
System.Threading.Timer Timer;
System.DateTime StopTime;
public void Run()
{
StopTime = System.DateTime.Now.AddMinutes(10);
Timer = new System.Threading.Timer(TimerCallback, null, 0, 5000);
}
private void TimerCallback(object state)
{
if(System.DateTime.Now >= StopTime)
{
Timer.Dispose();
return;
}
// Do your work...
}
}

Have your timer loop something like this:
DateTime endTime = DateTime.Now.AddMinutes(10);
while(endTime < DateTime.Now)
{
// Process loop
}

Divide the Y minutes by the X interval to get how many times it needs to run. After that you just need to count how many times the function has been called.
In your case, 10 min = 600 seconds / 5 seconds = 120 calls needed. Just have a counter keep track of how many times your function has been called.

Timer.Stop() after 120 Ticks.

just use a DateTime variable to track when it should end and set that right before you start. The on your Elapsed event handler, check if the signal time is less than the end time. If it isn't, stop the timer.

You can calculate how times your function will be call, and create decrement counter, after elapsed which you unsubscribe from timer tick. Or you can Run another timer which have tick period - 10 min and on tick you unsubscribe from timer tick calling your function.

Note the start time. In each call, test if currentTime + 5 seconds > startTime + 10 minutes. If so, disable the timer.
I prefer this approach to just running for N ticks, as timers are not guaranteed to fire when you'd like them to. It's possible 120 ticks may run over 10 minutes of real world time.

You can set two timers one that run for 5 secs and the other one that run for 10min and disable the first one

You could use a second timer:
class Program
{
static void Main(string[] args)
{
int interval = 5 * 1000; //milliseconds
int duration = 10 * 60 * 1000; //milliseconds
intervalTimer = new System.Timers.Timer(interval);
durationTimer = new System.Timers.Timer(duration);
intervalTimer.Elapsed += new System.Timers.ElapsedEventHandler(intervalTimer_Elapsed);
durationTimer.Elapsed += new System.Timers.ElapsedEventHandler(durationTimer_Elapsed);
intervalTimer.Start();
durationTimer.Start();
}
static void durationTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
intervalTimer.Stop();
durationTimer.Stop();
}
static void intervalTimer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
//call your method
}
private static System.Timers.Timer intervalTimer;
private static System.Timers.Timer durationTimer;
}