[RESOLVED] [2005] Format output of Stopwatch

[nbrege]

How can I format the output of the Stopwatch? I tried the following:

sw.Elapsed.ToString("mm:ss")

but VS complains. I would like to show just the minutes & seconds (to 3 decimal places) of the elapsed time. Thanks...

[Negative0]

The timespan does not provide an overrideable ToString method, so you are going to have to manually build the string:

MessageBox.Show(sw.Elapsed.Minutes.ToString("00") & ":" & sw.Elapsed.Seconds.ToString("00") & "." & sw.Elapsed.Milliseconds)

[jmcilhinney]

Dim elapsed As TimeSpan = myStopwatch.Elapsed
 
MessageBox.Show(String.Format("{0:00}:{1:00}.{2:000}", _
                              elapsed.TotalMinutes, _
                              elapsed.Seconds, _
                              elapsed.Milliseconds))

Notice that I used TotalMinutes and not Minutes. If you use Minutes then you'll never go past 59, so a value of an hour or more would show the incorrect time. Notice that I also forced the milliseconds to three figures, other wise 1 millisecond would be displaye as "00:00.1" instead of "00:00.001".

[Negative0]

Notice that I used TotalMinutes and not Minutes.

Nice catch.

[nbrege]

Thanks guys...

[nbrege]

Notice that I used TotalMinutes and not Minutes.

OK, I found a problem with using TotalMinutes. It rounds to the nearest whole minute, so an elapsed time of 31 seconds gets displayed as 01:31, whereas using Minutes displays 00:31, as it should be. Here is a little snippet that will demonstrate this:

Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        Me.Show()
        Dim sw As New Stopwatch

        sw.Start()
        System.Threading.Thread.Sleep(31000) 'sleep for 31 seconds
        sw.Stop()

        MessageBox.Show(String.Format("{0:00}:{1:00}.{2:000}", sw.Elapsed.Minutes, sw.Elapsed.Seconds, sw.Elapsed.Milliseconds) & ControlChars.CrLf & String.Format("{0:00}:{1:00}.{2:000}", sw.Elapsed.TotalMinutes, sw.Elapsed.Seconds, sw.Elapsed.Milliseconds))

    End Sub

[jmcilhinney]

Ah, sorry about that. I have used code like this before and I left a bit out. You do use TotalMinutes, not Minutes, but to account for the issue you mention you have to trucate the decimal part first. Change my code to this:

Dim elapsed As TimeSpan = myStopwatch.Elapsed
 
MessageBox.Show(String.Format("{0:00}:{1:00}.{2:000}", _
                              Math.Floor(elapsed.TotalMinutes), _
                              elapsed.Seconds, _
                              elapsed.Milliseconds))

The Math.Floor method will remove the decimal part of the value, thus ensuring it will never be rounded up.

[MHutcheon]

Ah, sorry about that. I have used code like this before and I left a bit out. You do use TotalMinutes, not Minutes, but to account for the issue you mention you have to trucate the decimal part first. Change my code to this:

Dim elapsed As TimeSpan = myStopwatch.Elapsed
 
MessageBox.Show(String.Format("{0:00}:{1:00}.{2:000}", _
                              Math.Floor(elapsed.TotalMinutes), _
                              elapsed.Seconds, _
                              elapsed.Milliseconds))

The Math.Floor method will remove the decimal part of the value, thus ensuring it will never be rounded up.

Can anyone explain please the quote code above works fine, but my code...

        ts = myStopWatch.Elapsed
        elapsedTime = ts.ToString(String.Format("{0:00}:{1:00}:{2:000}", Math.Floor(ts.TotalMinutes), ts.Seconds, ts.Milliseconds))
        Label8.Text = elapsedTime

... returns an error - System.FormatException: 'Input string was not in a correct format.' - on running please?

EDIT:

        ts = myStopWatch.Elapsed
        elapsedTime = String.Format("{0:00}:{1:00}:{2:000}", Math.Floor(ts.TotalMinutes), ts.Seconds, ts.Milliseconds)
        Label8.Text = elapsedTime

I didn't need the ts.ToString on line 2. All good now!