/// <summary>
/// Returns the union of all the selected range as Position collection
/// </summary>
/// <returns></returns>
public virtual CellCollection GetCells()
{
CellCollection cells = new CellCollection();
PositionCollection l_Positions = GetCellsPositions();
for (int i = 0; i < l_Positions.Count; i++)
{
cells.Add(m_Grid.GetCell(l_Positions[i]));
}
return(cells);
}