Converting Numbers To Words - Adding Decimal Support

Following a request today, here's a quick fix for adding decimal support to my article about 'Converting Numbers to Words using the Indian Numbering System (http://www.c-sharpcorner.com/UploadFile/b942f9/7480/#ReadAndPostComment) which, as it stands, only deals with integers:

using System;

class Program
{
    static void Main()
    {
       double d = 1234.5678;
       int i = (int)d;
       string decimalPart = d.ToString().Split('.')[1];     
       string text = NumberToText(i, true, false) + " Point" + DecimalToText(decimalPart);
       Console.WriteLine(text);
       Console.ReadKey();
    }


    public static string DecimalToText(string decimalPart)
    {
       string[] digits = {"Zero", "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine"};
       string result = "";
       foreach(char c in decimalPart)
       {
           int i = (int)c - 48;
           if (i < 0 || i > 9) return ""; // invalid number, don't return anything
           result += " " + digits[i];
       }
       return result;
    }

    public static string NumberToText(int number, bool useAnd, bool useArab)
    {
        if (number == 0) return "Zero";

        string and = useAnd ? "and " : ""; // deals with using 'and' separator

        if (number == -2147483648) return "Minus Two Hundred " + and + "Fourteen Crore Seventy Four Lakh Eighty Three Thousand Six Hundred " + and +"Forty Eight";

        int[] num = new int[4];
        int first = 0;
        int u, h, t;
        System.Text.StringBuilder sb = new System.Text.StringBuilder();

        if (number < 0)
        {
            sb.Append("Minus ");
            number = -number;
        }
        string[] words0 = {"" ,"One ", "Two ", "Three ", "Four ", "Five " ,"Six ", "Seven ", "Eight ", "Nine "};
        string[] words1 = {"Ten ", "Eleven ", "Twelve ", "Thirteen ", "Fourteen ", "Fifteen ", "Sixteen ", "Seventeen ", "Eighteen ", "Nineteen "};
        string[] words2 = {"Twenty ", "Thirty ", "Forty ", "Fifty ", "Sixty ", "Seventy ","Eighty ", "Ninety "};
        string[] words3 = { "Thousand ", "Lakh ", "Crore " };
        num[0] = number % 1000; // units
        num[1] = number / 1000;
        num[2] = number / 100000;
        num[1] = num[1] - 100 * num[2]; // thousands
        num[3] = number / 10000000; // crores
        num[2] = num[2] - 100 * num[3]; // lakhs
        for (int i = 3; i > 0; i--)
        {
            if (num[i] != 0)
            {
                first = i;
                break;
            }
        }

        for (int i = first; i >= 0; i--)
        {
            if (num[i] == 0) continue;

            u = num[i] % 10; // ones 
            t = num[i] / 10;
            h = num[i] / 100; // hundreds
            t = t - 10 * h; // tens

            if (h > 0) sb.Append(words0[h] + "Hundred ");
            if (u > 0 || t > 0)
            {
                if (h > 0 || i < first) sb.Append(and);

                if (t == 0)
                    sb.Append(words0[u]);
                else if (t == 1)
                    sb.Append(words1[u]);
                else
                    sb.Append(words2[t - 2] + words0[u]);
            }
            if (i != 0) sb.Append(words3[i - 1]);
        }

        string temp = sb.ToString().TrimEnd();

        if (useArab && Math.Abs(number) >= 1000000000)
        {
            int index = temp.IndexOf("Hundred Crore");
            if (index > -1) return temp.Substring(0, index) + "Arab" + temp.Substring(index + 13);
            index = temp.IndexOf("Hundred");
            return temp.Substring(0, index) + "Arab" + temp.Substring(index + 7);
        } 
        return temp;
    }
}