Timer won't tick

Question

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.

Answer 1

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();
}

Answer 2

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();
            }
        }

Answer 3

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
        {
            //
        }
    } 

}

Answer 4

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.