/// <summary>
/// Given a cell, parses the specified cell to get the column number.
/// </summary>
/// <param name="cell">Cell with reference (ie. C8)</param>
/// <returns>Column number (ie. 3)</returns>
public static int GetColumnNumber(this CellType cell)
{
var letter = cell.GetColumnLetter();
if (string.IsNullOrWhiteSpace(letter))
{
throw new ArgumentException("CellReference must be valid reference.");
}
letter = letter.ToUpperInvariant();
var sum = 0;
foreach (var c in letter.ToCharArray())
{
sum *= 26;
sum += (c - 'A' + 1);
}
return(sum);
}
