Develop Reference

Timer firing every second and updating GUI (C# Windows Forms)

I have a Windows Forms application where I need to have a timer working for 90 seconds and every second should be shown after it elapses, kind of like a stopwatch 1..2..3 etc, after 90 seconds is up, it should throw an exception that something is wrong.
I have the following code, but the RunEvent never fires.
private void ScanpXRF()
{
bool demo = false;
System.Windows.Forms.Timer timer = new System.Windows.Forms.Timer();
try
{
for (int timerCounter = 0; timerCounter < 90; timerCounter++)
{
timer.Interval = 1000;
timer.Tick += new EventHandler(RunEvent);
timer.Start();
if(timerCounter == 89) {
throw new Exception();
}
}
}
catch (Exception e)
{
timer.Dispose();
MessageBox.Show("There is a problem!");
}
}
private void RunEvent(object sender, System.EventArgs e)
{
//boxStatus.AppendText("RunEvent() called at " + DateTime.Now.ToLongTimeString() + "\n");
MessageBox.Show("timer fired!");
}
Is there anything I am doing wrong here or are there other suggestions for other ways to achieve the same result?

A timer needs to be declared at the form level, or else it may not be disposed of when the form closes:
System.Windows.Forms.Timer timer;
int counter = 0;
Your starting code should just start the timer:
private void ScanpXRF()
{
counter = 0;
timer = new System.Windows.Forms.Timer();
timer.Interval = 1000;
timer.Tick += RunEvent;
timer.Start();
}
The RunEvent is your Tick event being called every second, so your logic needs to go in there:
private void RunEvent(object sender, EventArgs e)
{
counter++;
if (counter >= 90) {
timer.Stop();
// do something...
}
}

made it work
private void ScanpXRF()
{
_pXRFTimerCounter = 0;
pXRFTimer.Enabled = true;
pXRFTimer.Interval = 1000;
pXRFTimer.Elapsed += new ElapsedEventHandler(pXRFTimer_Tick);
pXRFTimer.Start();
}
private static void pXRFTimer_Tick(Object sender, EventArgs e)
{
_pXRFTimerCounter++;
if (_pXRFTimerCounter >= 90)
{
pXRFTimer.Stop();
// do something...
}
else
{
MessageBox.Show(_pXRFTimerCounter.ToString() + " seconds passed");
}
}
I made the timer
System.Timers

How to use progressbar.value property at different locations of program

I need to use progressbar.value property at different locations. But the problem is, while executing it shows only maximum value given. I need to stop at 25% and 75% and after some delay, 100%. How can I overcome this problem. Thanks in Advance...
C#
namespace ProgressBarWindowForm
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
public void Form1_Load(object sender, System.EventArgs e)
{
label1.Hide();
progressBar1.Minimum = 0;
progressBar1.Maximum = 100;
}
private void button1_Click(object sender, EventArgs e)
{
progressBar1.Value = 25;
if (progressBar1.Value == 25)
{
label1.Show();
label1.Text = "Process Complete 25%";
}
progressBar1.Value = 75;
if (progressBar1.Value == 75)
{
label1.Show();
label1.Text = "Process Complete 75%";
}
}
}
}
Progressbar control name is progressBar1,
Label name is label1 and
Button name is button1
When I Clicked the Button, progressbar value is directly filling with 75%. I want to stop it at 25% and after some delay it should fill 75% and then 100%...Can anyone help..Can I use "progressBar1.value" only Once or as many times I need?

try this,Drag and drop background worker in windows form
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
backgroundWorker1.WorkerReportsProgress = true;
// This event will be raised on the worker thread when the worker starts
backgroundWorker1.DoWork += new DoWorkEventHandler(backgroundWorker1_DoWork);
// This event will be raised when we call ReportProgress
backgroundWorker1.ProgressChanged += new ProgressChangedEventHandler(backgroundWorker1_ProgressChanged);
}
private void button1_Click(object sender, EventArgs e)
{
// Start the background worker
backgroundWorker1.RunWorkerAsync();
}
// On worker thread so do our thing!
void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
// Your background task goes here
for (int i = 0; i <= 100; i++)
{
// Report progress to 'UI' thread
backgroundWorker1.ReportProgress(i);
// Simulate long task
if (label1.InvokeRequired)
{
label1.Invoke(new MethodInvoker(delegate
{
label1.Show();
label1.Text = "Process Complete " + progressBar1.Value + "%";
}));
}
if (progressBar1.Value == 25 || progressBar1.Value == 75)
{
System.Threading.Thread.Sleep(1000);
}
System.Threading.Thread.Sleep(100);
}
}
// Back on the 'UI' thread so we can update the progress bar
void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
// The progress percentage is a property of e
progressBar1.Value = e.ProgressPercentage;
}
}

Use a Timer to update the progress bar after a delay:
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
timer.Tick += Timer_Tick;
timer.Interval = 1000; // delay: 1000 milliseconds
}
Timer timer = new Timer();
private void Timer_Tick(object sender, EventArgs e)
{
if (progressBar1.Value == 100)
{
timer.Stop();
return;
}
progressBar1.Value += 25;
}
private void button1_Click(object sender, EventArgs e)
{
progressBar1.Value = 25;
timer.Start();
}
}

Its simple to update progressBar values in button click, you can initialize the properties in the page load or else use the designer, in page load it would be like the following:
private int ProgressPercentage = 10;
public void Form1_Load(object sender, System.EventArgs e)
{
progressBar1.Minimum = 0;
progressBar1.Maximum = 100;
progressBar1.Value = 0;
}
So the initialization completed, now you can code the button click like the following, through which you can update the progress bar in every button click:
private void button1_Click(object sender, EventArgs e)
{
progressBar1.Value += ProgressPercentage;
label1.Text = String.Format("Process Complete {0}%",progressBar1.Value);
}
If you want the update to be happens automatically in a particular interval means you can make use of a timer and enable the timer in the button click. Here you can find a similar thread which can be used to implement timer to your scene.
Update as per your comment, calling a delay will not be a best practice, you can make use a timer here as like the following:
System.Windows.Forms.Timer proTimer = new System.Windows.Forms.Timer();
private void Form1_Load(object sender, EventArgs e)
{
proTimer.Interval = 1000;
progressBar1.Minimum = 0;
progressBar1.Maximum = 100;
progressBar1.Value = 0;
proTimer.Tick += new EventHandler(proTimer_Tick);
}
private void button1_Click(object sender, EventArgs e)
{
proTimer.Enabled = true;
proTimer.Start();
}
// Timer event
void proTimer_Tick(object sender, EventArgs e)
{
progressBar1.Value += ProgressPercentage;
label1.Text = String.Format("Process Complete {0}%",progressBar1.Value);
if (progressBar1.Value == 100)
{
proTimer.Stop();
proTimer.Enbled = false;
}
}

You need to add a delay inbetween the changes. As of now, the button advance the bar to 25, sets the label, then advances the bar to 75 without pausing.
System.Threading.Thread.Sleep(n); will sleep n milliseconds, which you will need after the statement setting the 25 percent marker.
EDIT
If you want it the value to only progress on a button click, you will need to check the value of the progress bar before you advance it.
In pseudo code, something like:
onclick() {
if (progress == 0) {
progress = 25
label = the25MarkText
} else if (progress == 25) {
progress = 75
label = the75MarkText
}
}

Form timer doesn't start

So I just started learning C# and using forms. I have been able to create a digital clock and tinker with this and that, but now I'm trying to make a basic UI for a derpy game and my timer doesn't work.
First - what I'm trying to accomplish: A simple decrementing timer from 60 seconds (*clock style (mm:ss)).
Second, here's what I have:
public partial class Form1 : Form
{
private int counter = 60;
public Form1()
{
InitializeComponent();
label1.Text = TimeSpan.FromMinutes(1).ToString("m\\:ss");
}
private void pictureBox2_Click(object sender, EventArgs e)
{
}
private void timer1_Tick(object sender, EventArgs e)
{
counter--;
if (counter == 0)
{
timer1.Stop();
label1.Text = counter.ToString();
MessageBox.Show("Time's Up!!");
}
}
private void label1_Click(object sender, EventArgs e)
{
var startTime = DateTime.Now;
var counter = (TimeSpan.FromMinutes(1)).ToString("m\\:ss");
timer1 = new Timer();
timer1.Tick += new EventHandler(timer1_Tick);
timer1.Interval = 1000;
timer1.Start();
label1.Text = counter.ToString();
}
}
Appreciate the feedback and knowledge!

From the codes that I see, your timer is working but you are not updating it in each count, you are updating when the timer finishes -
private void timer1_Tick(object sender, EventArgs e)
{
counter--;
if (counter == 0)
{
timer1.Stop();
label1.Text = counter.ToString(); // *** Look here
MessageBox.Show("Time's Up!!");
}
}
You should update the timer in each tick, so take the update label code out of the if block -
private void timer1_Tick(object sender, EventArgs e)
{
counter--;
label1.Text = counter.ToString(); // should work
if (counter == 0)
{
timer1.Stop();
MessageBox.Show("Time's Up!!");
}
}
and also reset the counter in each cycle -
private void label1_Click(object sender, EventArgs e)
{
var startTime = DateTime.Now;
var counter = (TimeSpan.FromMinutes(1)).ToString("m\\:ss");
timer1 = new Timer();
timer1.Tick += new EventHandler(timer1_Tick);
timer1.Interval = 1000;
timer1.Start();
label1.Text = counter.ToString();
this.counter = 60
}
NOTE: I am really not sure if this code will throw any access
violation error, due to updating the UI in a different thread or not.
If so, then you have to use async/await or events/delegates to
update UI.
Let me know, if this throws error, then I will give you the async/await version.

This works fine for me. I would give progress updates as the time is countdown to show that it is working. For example, if you did this in label, you could do something like the following:
private void timer1_Tick(object sender, EventArgs e)
{
counter--;
label1.Text = counter.ToString();
if (counter == 0)
{
timer1.Stop();
MessageBox.Show("Time's Up!!");
}
}
Notice that the label1.Text = counter.ToString(); line has been moved before the counter == 0 check, so that it is able to provide feedback for all counter values.
As well, you may accidentally launch several timer1 instances if you do not keep track of how many you spawn using new Timer(). There are various ways to do this, but you could simply check whether timer1 already exists and counter == 0 before creating a new instance. You could perform this check as a guard clause (ie. return if either of those conditions are matched).
private void label1_Click(object sender, EventArgs e)
{
var startTime = DateTime.Now;
if (timer1 == null || (timer1 != null && counter == 0)) return;
counter = (TimeSpan.FromMinutes(1)).ToString("m\\:ss");
timer1 = new Timer();
timer1.Tick += new EventHandler(timer1_Tick);
timer1.Interval = 1000;
timer1.Start();
label1.Text = counter.ToString();
}
If you want this countdown to start automatically, you can put this directly into the constructor, or put it into another method and call it from the constructor like so:
public Form1()
{
InitializeComponent();
StartCountdown();
}
private void StartCountdown()
{
var startTime = DateTime.Now;
/* the rest of your original label1_Click code goes here ... */
}

WinForms sometimes appear twice and sometimes once

I am confuse at this one, the windows form called "Contact" sometimes called twice after the "Welcome Screen" and sometimes it ("Contact") is called once only. I am pretty sure that I called the form once only.
Here is the code that I am using:
The form below "WelcomeScreen" is the first one called when run the program:
public partial class WelcomeScreen : Form
{
int timeLeft = 5;
Timer _timer = new Timer();
BackgroundWorker _backgroundWorker = new BackgroundWorker();
public WelcomeScreen()
{
InitializeComponent();
_backgroundWorker.WorkerReportsProgress = true;
_backgroundWorker.DoWork += BackgroundWorker_DoWork;
_backgroundWorker.ProgressChanged += BackgroundWorker_ProgressChanged;
_timer.Interval = 1000;
_timer.Tick += Timer_Tick;
}
void WelcomeScreen_Load(object sender, EventArgs e)
{
_backgroundWorker.RunWorkerAsync();
}
void Timer_Tick(object sender, EventArgs e)
{
timeLeft--;
if (timeLeft <= 0)
{
_timer.Stop();
this.Hide();
Contact _contact = new Contact();
_contact.ShowDialog();
this.Close();
}
}
void BackgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
progressBar1.Value = e.ProgressPercentage;
if (e.ProgressPercentage <= 300)
{
_timer.Start();
this.label3.Text = "Completed ( " + timeLeft + " ) ";
this.label4.Text = string.Empty;
}
}
void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
for (int i = 0; i <= 300; i++)
{
_backgroundWorker.ReportProgress(i);
System.Threading.Thread.Sleep(200);
}
}
The form below "Contact" is called after the "WelcomeScreen":
public partial class Contact : Form
{
const int CP_NOCLOSE_BUTTON = 0x200;
public Contact()
{
InitializeComponent();
}
void Contact_Load(object sender, EventArgs e)
{
SystemManager.SoundEffect();
}
void button1_Click(object sender, EventArgs e)
{
this.Hide();
Loading _loading = new Loading();
_loading.ShowDialog();
this.Close();
}
protected override CreateParams CreateParams
{
get
{
CreateParams myCp = base.CreateParams;
myCp.ClassStyle = myCp.ClassStyle | CP_NOCLOSE_BUTTON;
return myCp;
}
}
I appreciate your answer!
Thank you

It looks like your Timer is causing the issue, by firing multiple times...
You have this condition inside your timer code:
if (timeLeft <= 0)
And the line before is timeLeft--. After timeLeft becomes 0, it will continue getting smaller (-1, -2, etc) and the form will be shown each time.
A quick fix is to either change the condition to timeLeft == 0 or change the type of timeLeft to a uint. Of course, these are both hacks. The correct fix would be to fix your code to stop the timer from firing when required.

Timer using label

So, this seems to be a common question but I can't seem to figure out a way to do this. I have a C# Form application that goes out to an imap client and processes the emails. I want to have a timer formatted like "08:45" (for 8 minutes and 45 seconds) displayed on the form to let the user know how long it has been since they clicked the button to start the process.
I want the timer to stop once my process ends obviously.
private void btn_ImportEmail_Click(object sender, EventArgs e)
{
this.timer = new System.Timers.Timer();
this.lblTimer = new System.Windows.Forms.Label();
((System.ComponentModel.ISupportInitialize) (this.timer)).BeginInit();
this.timer.Elapsed += new System.Timers.ElapsedEventHandler(this.OnTimerElapsed);
//connect to email and download messages...
this.timer.Enabled = true;
this.timer.SynchronizingObject = this;
timer.Interval = 1000;
timer.Start();
for (int I = 0 ; I <= messages.count() - 1; I++)
{
//process emails
}
timer.EndInit();
}
private void timer1_Tick(object sender, EventArgs e)
{
lblTimer.Text = DateTime.Now.ToString("mm:ss");
}
private void OnTimerElapsed(object sender, System.Timers.ElapsedEventArgs e)
{
lblTimer.Text = DateTime.Now.ToString("mm:ss");
// lblTimer.Text = string.Format("{0:mm:ss}", DateTime.Now);
}

The following SO Q/A might answer your question...
Display the running time of part of a program in a label
I would recommend changing the format to your needs.

The first thing that I see is that you are using DateTime.Now which will give you the current minutes and seconds, not elapsed minutes and seconds. The second thing and the main thing is that since you are processing your emails in your main UI's thread you are preventing your label from being updated, you would be better off looking at using a background worker instead.
Edit based on Idle_Mind's comment added DateTime Object instead of counter.
public partial class Form1 : Form
{
BackgroundWorker bgw = new BackgroundWorker();
Timer timer = new Timer();
DateTime startTime;
public Form1()
{
InitializeComponent();
timer.Interval = 1000;
timer.Tick += timer_Tick;
bgw.DoWork += bgw_DoWork;
bgw.RunWorkerCompleted+=bgw_RunWorkerCompleted;
}
void timer_Tick(object sender, EventArgs e)
{
label1.Text =((TimeSpan)DateTime.Now.Subtract(startTime)).ToString("mm\\:ss");
}
void bgw_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
timer.Stop();
}
void bgw_DoWork(object sender, DoWorkEventArgs e)
{
for (int I = 0 ; I <= messages.count() - 1; I++)
{
//process emails
}
}
private void button1_Click(object sender, EventArgs e)
{
bgw.RunWorkerAsync();
startTime = DateTime.Now;
timer.Start();
}
}