How to use timer

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how to use timer??
i have a form and whenever it load the current time should display
and update itself automatically. i try to use the code below but its showing this error.
"Cross-thread operation not valid: Control 'label5' accessed from a thread other than the thread it was created on."
sorry for silly question but i m new to c#. :)

C#

private void start_form_Load_1(object sender, EventArgs e)
{
    System.Timers.Timer timerClock = new System.Timers.Timer();
    timerClock.Elapsed += new ElapsedEventHandler(OnTimer);
    timerClock.Interval = 1000;
    timerClock.Enabled = true;
}

public void OnTimer(Object source, ElapsedEventArgs e)
{
    label5.Text = DateTime.Now.ToString();
}

[Corrected some code formatting]

Posted 6-Mar-10 9:15am

sam48

Updated 6-Mar-10 9:54am

Toli Cuturicu

v3

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Toli Cuturicu · Answer 1 · 2010-03-06T09:51:00

Solution 2

The previous answer you received is wrong.
You can do it in a very easy way.
You only need to use a System.Windows.Forms.Timer instead of your System.Timers.Timer.
That's All!

[Edit]
And, of course, the event should be Tick instead of OnTimer Elapsed.

Posted 6-Mar-10 9:51am

Toli Cuturicu

Updated 6-Mar-10 10:38am

v4

n_tar · Answer 2 · 2010-11-20T12:05:00

private void start_form_Load_1(object sender, EventArgs e)
{   
 System.Timers.Timer timerClock = new System.Timers.Timer();       
 timerClock.Elapsed += new ElapsedEventHandler(OnTimer);    
 timerClock.Interval = 1000;   
 timerClock.Enabled = true;
}
public void timer1_Tick(object sender, EventArgs e)
{   
 label5.Text = DateTime.Now.ToString();
}

Abhinav S · Answer 3 · 2010-03-06T09:27:00

Solution 1

A timer runs on a separate thread. You cannot access a label property within the thread.

You need to use BeginInvoke. For a solution see here[^].

Posted 6-Mar-10 9:27am

Abhinav S