C#

$('#dts_start').datetimepicker(
    {
        showWeek:true,
        showSecond: true,
        dateFormat: "dd/mm/yy",
        timeFormat: "hh:mm:ss",
        yearRange: "-500:+10",
        changeMonth: true,
        changeYear: true
    }
);

var timer = new DispatcherTimer
               {
                   Interval = new TimeSpan(0, 0, 3)//3 seconds
               };
           timer.Tick += timer_Tick;//Subscribe to a method which have functionality to run after Idle time.

void timer_Tick(object sender, object e)
       {
           //Do your operation
       }

timer.Start(); 

OriginalGriff wrote:

With serial data, you will get a DataReceived event fired when there is one of more characters received by the computer: it will not wait until they have all been read, because it does not know when the message ends.

void arduinoBoard_DataReceived(object sender, SerialDataReceivedEventArgs e)
{
    string data = arduinoBoard.ReadTo("\x03");//Read until the EOT code
    //Split into 'date=temperature' formatted text
    string[] dataArray = data.Split(new string[]
    {"\x02", "$" }, StringSplitOptions.RemoveEmptyEntries);
    //Iterate through the split data and parse it into weather data items
    //and add them to the list of received weather data.
    foreach (string dataItem in dataArray.ToList())
    {
       WeatherDataItem weatherDataItem = new WeatherDataItem();
       weatherDataItem.FromString(dataItem);
       weatherDataItems.Add(weatherDataItem);
     }

     if(NewWeatherDataReceived != null)//If there is someone waiting for this event to be fired
     {
       NewWeatherDataReceived(this, new EventArgs()); //Fire the event,
            // indicating that new WeatherData was added to the list.
     }
}