private int ParseInternalInterval(string s, int index, NoteContext context)
{
if (context.IsRest)
{
return(index);
}
// An internal interval is indicated by a single quote
if ((index < s.Length) && (s[index] == '\''))
{
int intervalLength = 0;
// Verify that index+1 is a number representing the interval.
if (index + 1 < s.Length && IsValidIntervalChar(s[index + 1]))
{
intervalLength = 1;
}
// We'll allow for the possibility of double-sharps and double-flats.
if ((intervalLength == 1) && (index + 2 < s.Length) && IsValidIntervalChar(s[index + 2]))
{
intervalLength = 2;
}
if ((intervalLength == 2) && (index + 3 < s.Length) && IsValidIntervalChar(s[index + 3]))
{
intervalLength = 3;
}
context.InternalInterval = Intervals.GetHalfsteps(s.Substring(index + 1, intervalLength));
context.OriginalString = Note.ToneStringWithoutOctave((context.NoteNumber + context.InternalInterval)) + (context.IsOctaveExplicitlySet ? context.OctaveNumber.ToString() : "");
return(index + intervalLength + 1);
}
return(index);
}