/// <summary>
/// -SERVICE- if both start and end cells are set, we can guess the reading direction
/// </summary>
private void setDirection()
{
if(startCell==null || endCell==null)
throw new InvalidOperationException("Both starting and ending cells should be set before determining the direction");
if (startCell.Row != endCell.Row && startCell.Column != endCell.Column)
throw new ArgumentException("The starting and the ending cells should be equal in row or column number.");
int direction = 0;
direction += Math.Sign(endCell.Column - startCell.Column) * 3;
direction += Math.Sign(endCell.Row - startCell.Row);
this.direction = (ExcelReadDirection)direction;
return;
}
