method to display float in datetime format

Question

I need a method in c# that makes me a string that look like a datetime out of a double/float.

for example

1.5 -> 01:30 2.8 -> 02:48 25.5 -> 25:30 (note: don't display as day, display full hours even its more than 24)

Answer 1

It sounds to me like you don't want a DateTime - you want a TimeSpan:

TimeSpan ts = TimeSpan.FromMinutes(x);

or

TimeSpan ts = TimeSpan.FromHours(x);

(depending on your exact requirement).

Note that "2.8" won't be exactly 2.8, so you may not get exactly the result you expect - for the normal reasons of floating point bases etc.

Although there's no custom formatting for TimeSpan values in currently released version of the framework, it's coming in .NET 4.0.

Answer 2

Try the following:

string ToTime(double hours)
{
    var span=TimeSpan.FromHours(hours);
    return string.Format("{0}:{1:00}:{2:00}",
        (int)span.TotalHours, span.Minutes, span.Seconds);
}

Or if you don't want seconds:

string.Format("{0}:{1:00}", (int)span.TotalHours, span.Minutes)

Answer 3

string convert(double time)
{
    int hours = (int)Math.Floor(time);
    int minutes = Convert.ToInt32( (time-Math.Floor(time)) * 60 );

    return String.Format( "{0}:{1}", hours, minutes );
}