in c#, how can i build up array from A to ZZ that is similar to the way that excel orders columns

Question

i am looking for code that can generate an array where the first item is A, then B, then C . . .after Z i

Answer 1

class Program
{
    public static string IntegerToExcelColumn(int col)
    {
        // I've put a 256 upper bound here because Excel 2003 
        // allows only 256 columns. Change it if you're using 
        // Excel 2007 or 2010.
        Debug.Assert(col >= 1 && col <= 256);

        if (col >= 1 && col <= 26)
        {
            return ((char)(((int)'A') + (col - 1))).ToString();
        }

        // I've put a 256 upper bound here because Excel 2003 
        // allows only 256 columns. Change it if you're using 
        // Excel 2007 or 2010.
        if (col > 26 && col <= 256)
        {
            int rem = col % 26;
            int pri = col / 26;
            if (rem == 0)
            {
                rem = 26;
                pri--;
            }
            char[] buffer = new char[2];
            buffer[0] = (char)(((int)'A') + (pri - 1));
            buffer[1] = (char)(((int)'A') + (rem - 1));
            return new string(buffer);
        }

        return "";
    }

    static void Main(string[] args)
    {
        string[] columns= new string[255];
        for (int i = 1; i <= 255; i++)
            columns[i-1] = IntegerToExcelColumn(i);
        foreach(var col in columns)
            Console.WriteLine(col);
    }
}