private static int getColumnNumber(string columnName)
{
char[] chars = columnName.ToCharArray();
if (chars.Length == 1)
{
int colNr1 = (int)(chars[0] - 64);
return colNr1;
}
else if (chars.Length == 2)
{
int colNr1 = (int)(chars[1] - 64);
int colNr2 = (int)(chars[0] - 64);
return colNr1 + (26 * colNr2);
}
else if (chars.Length == 3)
{
int colNr1 = (int)(chars[2] - 64);
int colNr2 = (int)(chars[1] - 64);
int colNr3 = (int)(chars[0] - 64);
return colNr1 + (26 * colNr2) + (26 * 26 * colNr3);
}
else
{
return -1;
}
}