[RESOLVED] [2005] How to use the Timer or Stopwatch Class to timeout in 30 seconds

[IkeConn]

Hello,

Nothing I have found on the Stopwatch Class shows how to watch for X seconds elapsed time in a piece of code. It seems to be generally used for performance measurements.

What I'm doing is grabbing data from a serial port, which works, but it can't handle a connection that doesn't send data so I want to time out the serial port based on nothing happening for say 30 seconds.

What I need is code that will do something like this pseudo-code:


Do Until SerialPort.BytesToRead >= XXXX or timeOut = 1

start stopwatch
when 30 seconds elapses set variable timeOut = 1 'to be used in Do test
stop stopwatch

<other stuff here/>

Loop


Thanks,

Ike

[stanav]

stopwatch isn't the right class for what you're trying to do. You should user a timer instead, and set its interval to 30000 (30 seconds). Then in the timer.Tick event, you set the variable timeOut.

[IkeConn]

I ended up using a timer inside a sub that fires on a SerialPort1.PinChanged event and looks for Carrier Detect to raise. Then the code starts a timer that fires in 15 seconds (more or less) which triggers the OnBadConnectionFound sub which resets the port.



Public Sub TimeOutBadConnection(ByVal sender As Object, _
ByVal e As System.IO.Ports.SerialPinChangedEventArgs) _
Handles SerialPort1.PinChanged
Dim portTimer As New System.Timers.Timer()
AddHandler portTimer.Elapsed, AddressOf OnBadConnectionFound
If SerialPort1.CDHolding = True And SerialPort1.BytesToRead = 0 Then
portTimer.Enabled = True
portTimer.Interval = 15000
portTimer.AutoReset = False
GC.KeepAlive(portTimer)
End If
End Sub
Public Sub OnBadConnectionFound(ByVal Source As Object, ByVal e As System.Timers.ElapsedEventArgs) ' Handles portTimer.Elapsed
resetPort()
End Sub

Regards,

Ike