protected override bool DoExecute()
{
_oldCells = Canvas.Cells.Where(c => c.Brush.Shape != ' ').ToArray();
Unnotate(_oldCells);
_newCells = GetAnnotations();
Canvas.Annotate(_newCells);
return(!_oldCells.SequenceEqual(_newCells));
}
private bool Reannotate(Cell[] from, Cell[] to)
{
if (from.SequenceEqual(to))
{
return(false);
}
Unnotate(from);
Canvas.Annotate(to);
return(true);
}
private void Unnotate(IEnumerable <Cell> cells)
{
Canvas.Annotate(cells.Select(c => c.Clone(' ')).ToArray());
}