So I’ve got this auto-incrementing C# TimeSpan that I need to format to just show single minutes and seconds, e.g. 3:48.

var timeSpan = new TimeSpan(0, 0, 0, secondsElapsed++);

Bugger took a while to figure out because I kept trying things like “m:ss” in my string formatter, not catching on that, just as in a Regex expression, I need to escape the colon. That can be done either by:

var timeStr = String.Format("{0:m\:ss}", timeSpan);

or:

var timeStr1 = String.Format(@"{0:m:ss}", timeSpan);

I find that things like this take longer to figure out not because I don’t know how to do them, but because I have these preconceived notions of how they’re supposed to be done. Ordinarily, a string formatter is very forgiving of input so I expected it to “just work” in a certain way.

On another note, displaying a timer looks much better if you use a mono-spaced font. Otherwise, the number jump around as they change. Since this is being used in a Windows Phone app, I set the text block like this:

<TextBlock Name="TBlockTimerDisplay" TextAlignment="Right" FontSize="36" FontFamily="Segoe UI Mono"/>

THere are a couple other typefaces, such as Courier New, included with Windows Phone, but Segoe UI Mono would be my first choice, since it matches the default typeface for the OS.