I would like to slow down a loop so that it loops every 5 seconds.
In ActionScript, I would use a timer and a timer complete event to do this. How would I go about it in C#?
You can add this call inside your loop:
System.Threading.Thread.Sleep(5000); // 5,000 ms
or preferable for better readability:
System.Threading.Thread.Sleep(TimeSpan.FromSeconds(5));
However, if your application has a user interface you should never sleep on the foreground thread (the thread that processes the applications message loop).
You can try using Timer,
using System;
public class PortChat
{
public static System.Timers.Timer _timer;
public static void Main()
{
_timer = new System.Timers.Timer();
_timer.Interval = 5000;
_timer.Elapsed += new System.Timers.ElapsedEventHandler(_timer_Elapsed);
_timer.Enabled = true;
Console.ReadKey();
}
static void _timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
//Do Your loop
}
}
Also if your operation in loop can last more then 5 sec, You can set
_timer.AutoReset = false;
to disable next timer tick until operation finish in loop
But then end end of loop You need again to enable timer like
_timer.Enabled = true;
Don't use a loop at all. Set up a Timer object and react to its fired event. Watch out, because these events will fire on a different thread (the timer's thread from the threadpool).
Let's say you have a for-loop that you want to use for writing to a database every second. I would then create a timer that is set to a 1000 ms interval and then use the timer the same way you would use a while-loop if you want it to act like a for-loop. By creating the integer before the loop and adding to it inside it.
public patial class Form1 : From
{
timer1.Start();
int i = 0;
int howeverLongYouWantTheLoopToLast = 10;
private void timer1_Tick(object sender, EventArgs e)
{
if (i < howeverLongYouWantTheLoopToLast)
{
writeQueryMethodThatIAssumeYouHave(APathMaybe, i); // <-- Just an example, write whatever you want to loop to do here.
i++;
}
else
{
timer1.Stop();
//Maybe add a little message here telling the user the write is done.
}
}
}
Related
I have a little problem. There is something like chess timer. When i press button, current timer stops and second starts, but after 1 second. How can i start second one immediately?
using System;
using System.Windows.Forms;
namespace WindowsFormsApp1 {
public partial class Form1 : Form {
byte sec1;
byte sec2;
public Form1() {
InitializeComponent();
sec1 = 0;
sec2 = 0;
}
private void button1_Click(object sender , EventArgs e) {
timer1.Start();
timer2.Stop();
}
private void button2_Click(object sender , EventArgs e) {
timer2.Start();
timer1.Stop();
}
private void timer1_Tick(object sender , EventArgs e) {
label1.Text = sec1.ToString();
sec1++;
}
private void timer2_Tick(object sender , EventArgs e) {
label2.Text = sec2.ToString();
sec2++;
}
}
}
Edit
I know your question is "how to start the timers immediately", but in your code they are starting immediately. When you call start the timer starts. I believe the effect you are seeing is related to the delay associated with the tick event, which from the description I am assuming is set to a 1 second interval. Since you have said that you are trying to simulate something similar to a chess timer (although in your case counting up as opposed to down), then using something like a stop watch which can start, stop and show elapsed time would be a closer model. Since there is a Stopwatch class that provides exactly this behavior, I think it would be easier to implement it using two of those and just have a single background thread that updates the UI as frequently as needed. You could even add an update call into each button push to ensure the text boxes are up to date.
===============================
Maybe instead of the timers you should use two instances of the Stopwatch class. This will remove the need for your two variables that you are using to keep track of the seconds as the Stopwatch class will be holding the elapsed time for each counter.
Then in your button methods you could just do this:
private Stopwatch sw1 = new Stopwatch();
private Stopwatch sw2 = new Stopwatch();
private void button1_Click(object sender , EventArgs e) {
sw1.Start();
sw2.Stop();
}
private void button2_Click(object sender , EventArgs e) {
sw2.Start();
sw1.Stop();
}
And then you can use a Background worker or some other background thread that runs and updates your text boxes with the elapsed time from the timers you just need to grab the elapsed time.
// This will give you the total number of seconds elapsed.
var timer1Seconds = Math.Floor(sw1.Elapsed.TotalSeconds);
Here is an example of how you can make this update the UI:
private bool _stop = false;
public Form1()
{
InitializeComponent();
Task.Run(() =>
{
while(!_stop)
{
UpdateElapsedTimes();
Thread.Sleep(1000);
}
}
}
private void UpdateElapsedTimes()
{
if (InvokeRequired)
{
Invoke(UpdateElapsedTimes());
return;
}
label1.Text = Math.Floor(sw1.Elapsed.TotalSeconds).ToString();
label2.Text = Math.Floor(sw2.Elapsed.TotalSeconds).ToString();
}
Note - in a production program I would not use a boolean as my loop checker, you would use an event handle, and probably a couple of event handles if you wanted to allow pausing the updates, this is just to show an idea of how to do it. You could invoke directly from the thread method and drop the InvokeRequired check, but I added that for additional safety and since it was there I skipped it in the loop.
The timer does start immediately. The problem is that you are not reporting fractions of seconds, so the display will show 0 until a full second has elapsed, which is accurate, technically.
If you want to show 1 immediately, just initialize your variables that way.
public Form1() {
InitializeComponent();
sec1 = 1;
sec2 = 1;
}
How do I execute an infinite loop in C# with a 1 minute delay per iteration?
Is there any way to do it without using some kind of variable with x++ and setting x to some incredibly large number?
Solution1 :
If you want to wait for 1 minute without hanging your Main Thread, it is good to use Timer Control.
Step 1: You need to Subscribe to the Timer Tick event.
Step 2: Set the Interval property of the Timer to 60000 milliseconds for raising the event for every Minute.
Step 3: In Tick Event Handler just do ehatever you want to perform.
Step 4: you can Call the timer1.Stop() method whenever you want to stop the timer.
Note : if you don't stop the timer it becomes infinite.
if you want to stop the timer you can call timer1.Stop();
System.Windows.Forms.Timer timer1 = new System.Windows.Forms.Timer();
timer1.Interval=60000;//one minute
timer1.Tick += new System.EventHandler(timer1_Tick);
timer1.Start();
private void timer1_Tick(object sender, EventArgs e)
{
//do whatever you want
}
Solution 2:
EDIT : From the below comments : if the OP(Original Poster) is Trying to run this from Console Application System.Timers.Timer can be used
Note : instead of Handling Tick Event , OP has to handle the Elapsed Event.
Complete Code:
class Program
{
static System.Timers.Timer timer1 = new System.Timers.Timer();
static void Main(string[] args)
{
timer1.Interval = 60000;//one minute
timer1.Elapsed += new System.Timers.ElapsedEventHandler(timer1_Tick);
timer1.Start();
Console.WriteLine("Press \'q\' to quit the sample.");
while (Console.Read() != 'q') ;
}
static private void timer1_Tick(object sender, System.Timers.ElapsedEventArgs e)
{
//do whatever you want
Console.WriteLine("I'm Inside Timer Elapsed Event Handler!");
}
}
while (true)
{
System.Threading.Thread.Sleep(60000);
}
Now if we assume you don't want this thread to block and you're ok dealing with threading concerns, you can do something like this:
System.Threading.Tasks.Task.Run(() =>
{
while (true)
{
// do your work here
System.Threading.Thread.Sleep(60000);
}
});
The Task will put your work on a ThreadPool thread, so it runs in the background.
You can also look at a BackgroundWorker if that's more geared toward what you want.
for(;;)
{
//do your work
Thread.Sleep(60000);
}
This is not optimal but does exactly what it's asked.
From a similar question on MSDN:
>
System.Threading.Thread.Sleep(5000);
this codes make your application waiting for 5 seconds.
Change the number as necessary for the amount of time you want to sleep for (for one minute, this would be 60000).
You can put this where you want in your while loop
while(true){
Sleep(60000);}
This would be a blocking call, so you would want to put it on its own thread or any kind of UI that you would have would hang badly.
Sleep is in the System.Threading.Thread namespace.
I have an application that generates random numbers for about 20 seconds and shows the random number on the fly in a label in the screen.
I want to show the numbers in the same label but then slow down the display of the numbers so like 5 seconds before stoping the process, the display of the number should smoothly slow down more and more until it stops in the final number. Like a raffle.
Any clue?
I can start by telling you what not do to. Do not use Thread.Sleep -- doing so is almost always a "worst practice" and will make your UI unresponsive.
If you use Thread.Sleep on a second thread, as mcl suggests, you won't freeze your UI but you are burning an extremely expensive thread to do very little work.
If you are using C# 4 or earlier then I would create a timer set to tick, say, four times a second. Handle the tick event, and if enough time has passed since the last tick event, change the label. Or, change the interval of the timer each time it ticks.
If you are using C# 5, you can just use await Task.Delay(x):
async void Animate()
{
int delay = 5;
for(int i = 1; i < 10; ++i)
{
UpdateLabel();
await Task.Delay(delay);
delay = delay * 2;
}
}
So now you start with a 5ms delay, then 10, then 20...
Here's a working program to get you started. It changes the Text of the Form for 3 seconds quickly, after which it gets slower. That's achieved by using one Timer to start decelerating the Timer which shows the random numbers.
public partial class Form1 : Form
{
System.Windows.Forms.Timer timer = new System.Windows.Forms.Timer() { Interval = 10 };
System.Windows.Forms.Timer timerForStartingSlowDown = new System.Windows.Forms.Timer() { Interval = 3000 };
bool slow = false;
Random random = new Random();
public Form1()
{
InitializeComponent();
timer.Tick += timer_Tick;
timerForStartingSlowDown.Tick += timerForStartingSlowDown_Tick;
Shown += Form1_Shown;
}
void timerForStartingSlowDown_Tick(object sender, EventArgs e)
{
slow = true;
timerForStartingSlowDown.Enabled = false;
}
void Form1_Shown(object sender, EventArgs e)
{
timer.Enabled = true;
timerForStartingSlowDown.Enabled = true;
}
void timer_Tick(object sender, EventArgs e)
{
if (timer.Interval > 350) timer.Enabled = false;
else
{
if (slow) timer.Interval += 10;
Text = random.Next(1, 100).ToString();
}
}
}
Consider generating those numbers on a different thread. You can use BackgroundWorker for that and report the progress as you generate each number. When you begin to reach the end use Thread.Sleep(miliseconds) to "slow" (freez) the BackgroundWorker's job thread that is generating the numbers for a specified amount of miliseconds increasing those miliseconds as you aproach the final number. That should do the trick.
http://msdn.microsoft.com/en-us/library/system.componentmodel.backgroundworker.aspx
Set the BackgroundWorker to report progress and use that to "push" the generated number to the UI thread.
You can also drag and drop the BackgroundWorker component on your form from the Toolbox.
I have a statusbar label and I want to show a text on my StatusBar Label for 3 seconds only
How can I do it without using threads?
public void InfoLabel(string value)
{
if (InvokeRequired)
{
this.Invoke(new Action<string>(InfoLabel), new object[] { value });
return;
}
infoLabel.Text = value;
}
Simply add timer on the end of your method:
if (!string.IsNullOrWhiteSpace(value))
{
System.Timers.Timer timer = new System.Timers.Timer(3000) { Enabled = true };
timer.Elapsed += (sender, args) =>
{
this.InfoLabel(string.Empty);
timer.Dispose();
};
}
You need to define a function that you call each time you need to display your text, inside this function you define a timer, this timer is based on System.Windows.Forms.Timer, the only difference is that its modified to hold a stopTime parameter that represents the running duration, the only thing you need to do is to put your starting code(display text) inside the MyFunction function and to put the ending code(to stop displaying text) inside the Timer_Tick function, once you call MyFunction just specify how many seconds you want it to run in the function parameter.
private void MyFunction(int durationInSeconds)
{
MyTimer timer = new MyTimer();
timer.Tick += new EventHandler(Timer_Tick);
timer.Interval = (1000) * (1); // Timer will tick every second, you can change it if you want
timer.Enabled = true;
timer.stopTime = System.DateTime.Now.AddSeconds(durationInSeconds);
timer.Start();
//put your starting code here
}
private void Timer_Tick(object sender, EventArgs e)
{
MyTimer timer = (MyTimer)sender;
if (System.DateTime.Now >= timer.stopTime)
{
timer.Stop();
//put your ending code here
}
}
the modified timer class
public class MyTimer : System.Windows.Forms.Timer
{
public System.DateTime stopTime;
public MyTimer()
{
}
}
You can use Timer to create an instance of a timer that waits for n seconds before firing the Elapsed event. In the elapsed event, you clear the label's Content.
As the timer is executed in a separate thread, the UI thread is not locked while the timer is counting i.e. you are free to perform other operations in the UI.
private delegate void NoArgDelegate();
private void StartTimer(int durationInSeconds)
{
const int milliSecondsPerSecond = 1000;
var timer = new Timer(durationInSeconds * milliSecondsPerSecond);
timer.Start();
timer.Elapsed += timer_Elapsed;
}
private void timer_Elapsed(object sender, ElapsedEventArgs e)
{
var clearLabelTextDelegate = new NoArgDelegate(ClearLabelText);
this.Dispatcher.BeginInvoke(clearLabelTextDelegate);
}
private void ClearLabelText()
{
this.myLabel.Content = string.Empty;
}
As I do not the rest of your code, some suggestions would be to create a lock on the timer so as to prevent more than one UI event starting the timer. In addition, the delegate and the timer instance can be made as private members of the class.
You'll always be using at least the GUI thread. If you decide to wait on that thread, no other interaction with controls is possible (ie. no buttons will work, the window will not be repainted).
Alternatively you could use a System.Windows.Forms.Timer that gives control back to the OS, or another type of timer. Either way, the "countdown" will either block user interaction or happen on another thread (under the hood).
I have a Console App and in the main method, I have code like this:
Timer time = new Timer(seconds * 1000); //to milliseconds
time.Enabled = true;
time.Elapsed += new ElapsedEventHandler(time_Elapsed);
I only want the timer to run once so my idea is that I should stop the timer in the time_Elapsed method. However, since my timer exists in Main(), I can't access it.
You have access to the Timer inside of the timer_Elapsed method:
public void timer_Elapsed(object sender, ElapsedEventArgs e)
{
Timer timer = (Timer)sender; // Get the timer that fired the event
timer.Stop(); // Stop the timer that fired the event
}
The above method will stop whatever Timer fired the Event (in case you have multiple Timers using the same handler and you want each Timer to have the same behavior).
You could also set the behavior when you instantiate the Timer:
var timer = new Timer();
timer.AutoReset = false; // Don't reset the timer after the first fire
A little example app:
static void Main(string[] args)
{
int seconds = 2;
Timer time = new Timer(seconds * 1000); //to milliseconds
time.Enabled = true;
time.Elapsed += new ElapsedEventHandler(MyHandler);
time.Start();
Console.ReadKey();
}
private static void MyHandler(object e, ElapsedEventArgs args)
{
var timer = (Timer) e;
timer.Stop();
}
I assume that you're using System.Timers.Timer rather than System.Windows.Forms.Timer?
You have two options.
First, as probably the best, is to set the AutoReset property to false. This should do exactly what you want.
time.AutoReset = false;
The other option is to call Stop in the event handler.
You may also use the System.Threading.Timer. Its constructor takes two time-related parameters:
The delay before the first "tick" (due time)
The period
Set the period to Timeout.Infinite to prevent from firing again.