private static bool PreviousUnit(int start, ITextRange subrange, TomUnit unit)
{
if (subrange.Start <= start)
{
return false;
}
else
{
// collapse the range to the end and then extend it another unit.
subrange.Collapse(TomStartEnd.tomStart);
subrange.MoveStart(unit, -1);
// truncate if necessary to ensure it fits inside the range
if (subrange.Start < start)
{
subrange.Start = start;
}
return true;
}
}
private static bool NextUnit(int end, ITextRange subrange, TomUnit unit)
{
if (subrange.End >= end)
{
return false;
}
else
{
// collapse the range to the end and then extend it another unit.
subrange.Collapse(TomStartEnd.tomEnd);
subrange.MoveEnd(unit, 1);
// truncate if necessary to ensure it fits inside the range
if (subrange.End > end)
{
subrange.End = end;
}
return true;
}
}