How to change label content with timers throwing InvalidOperationException

.net, c#, multithreading, timer, wpf

Solution

For .NET 4.0 it is much simpler to use a DispatcherTimer. The eventhandler is then in the UI thread and it can set properties of the control directly.

private DispatcherTimer updateTimer;

private void initTimer
{
     updateTimer = new DispatcherTimer(DispatcherPriority.SystemIdle); 
     updateTimer.Tick += new EventHandler(OnUpdateTimerTick);
     updateTimer.Interval = TimeSpan.FromMilliseconds(1000);
     updateTimer.Start();
}

private void OnUpdateTimerTick(object sender, EventArgs e)
{
    lblTimer.Content = "hello";
}

Problem

I'm making an application and I'm using a timer in that application to change label content in WPF C# .NET. In the timer's elapsed event I'm writing the following code ``` lblTimer.Content = "hello"; ``` but its throwing an `InvalidOperationException` and gives a message The calling thread cannot access this object because a different thread owns it. I'm using .NET framework 3.5 and WPF with C#. Please help me. Thanks in advance.

Original source