/// <summary>
/// Tries to parse a string as a <see cref="MeasureUnit"/> and registers it in this context
/// on success.
/// </summary>
/// <param name="s">The string to parse. Must not be null.</param>
/// <param name="u">On success, the unit of measure.</param>
/// <returns>True on success, false if the string can not be parsed as a measur of unit.</returns>
public bool TryParse(string s, out MeasureUnit u)
{
if (s == null)
{
throw new ArgumentNullException(nameof(s));
}
// 1 - Normalize input by removing all white spaces.
// Trust the Regex cache for this quite common one.
s = Regex.Replace(s, "\\s+", String.Empty);
if (_allUnits.TryGetValue(s, out u))
{
return(true);
}
Match match = _rUnit.Match(s);
if (!match.Success)
{
return(false);
}
var all = new List <ExponentMeasureUnit>();
do
{
if (!TryParseExponent(match, out var e))
{
return(false);
}
if (e != MeasureUnit.None)
{
all.Add(e);
}
match = match.NextMatch();
}while(match.Success);
u = MeasureUnit.Combinator.Create(this, all);
return(true);
}
/// <summary> /// Tries to parse a string in the default context (<see cref="StandardMeasureContext.Default"/>). /// </summary> /// <param name="text">The text to parse.</param> /// <param name="u">The resulting measure unit.</param> /// <returns>True on success, false otherwise.</returns> public static bool TryParse(string text, out MeasureUnit u) => StandardMeasureContext.Default.TryParse(text, out u);
/// <summary>
/// Initializes a new <see cref="Quantity"/>.
/// </summary>
/// <param name="v">Quantity value.</param>
/// <param name="unit">Unit of measure. Can be null (<see cref="MeasureUnit.None"/> is used).</param>
public Quantity(double v, MeasureUnit unit)
{
Value = v;
_unit = unit ?? MeasureUnit.None;
_normalized = null;
}
/// <summary> /// Constructs a new <see cref="Quantity"/> from a double. /// </summary> /// <param name="this">This double.</param> /// <param name="u">The unit of the measure of the quantity.</param> /// <returns>The quantity.</returns> public static Quantity WithUnit(this double @this, MeasureUnit u) => new Quantity(@this, u);
void ThrowArgumentException(MeasureUnit m, string explain)
{
throw new ArgumentException($"Already existing unit registration (context '{Name}') for '{m.ToString()}': " + explain);
}
