How do you parse a time string with unit (us, ms, s, etc.) to TimeSpan

[alexandreperr]

Hi folks,

I am willing to create a TypeConverter that allows converting a string in a TimeSpan.
The thing is I want to be able to enter a time with units such as:
75ms or m
125us or u
0.25s

I don't really know what to use for parsing the string.
I would like to use RegEx but I can't figure what format to use.

So far I have this structure of Converter:

	public class TimeConverter : TypeConverter
	{

		public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
		{
			if (sourceType == typeof(string))
				return true;
			return base.CanConvertFrom(context, sourceType);
		}

		public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
		{
			if (destinationType == typeof(InstanceDescriptor))
				return true;
			return base.CanConvertTo(context, destinationType);
		}

		public override object ConvertFrom(ITypeDescriptorContext context,
			System.Globalization.CultureInfo culture, object value)
		{
			if (value is string)
			{
				string str = ((string)value);
				TimeSpan ts;

				ts = TimeSpan.Parse(str);

				return ts;
			}
			return base.ConvertFrom(context, culture, value);
		}

		// Overrides the ConvertTo method of TypeConverter.
		public override object ConvertTo(ITypeDescriptorContext context,
		   System.Globalization.CultureInfo culture, object value, Type destinationType)
		{
			return base.ConvertTo(context, culture, value, destinationType);
		}
	}

Thanks for your help.

Alex

[Christian Binder]

I think, the simplest way would be if the last character are m, s, u ms or us.
And if its one of these check the previous string (without time-unit) if it's a number.
I don't know much about RegEx, so I would do it this way.
E.g.

string timestr = 125us;
double timevalue;
if(timestr.EndsWith("us") && double.TryParse(timestr.Substring(0, timestr.Length - 2), out timevalue)) {
  //create timespan
} else if(timestr.EndsWiths("s") && double.TryParse(timestr.Substring(0, timestr.Length - 1), out timevalue)) {
  //create timespan
}
else if //...