Represent a number string as verbose

VerboseNumberExample.cs

using System;
using System.IO;
using System.Collections.Generic;
using System.Text;
using System.Diagnostics;
using System.Linq;

public static class Program
{
    static void Main()
    {
        using (StreamReader reader = new StreamReader(Console.OpenStandardInput()))
            while (!reader.EndOfStream)
            {
                string line = reader.ReadLine();
                //Debug.WriteLine(VerboseNumber("1"));            // OneDollars (always represent as Plural)
                //Debug.WriteLine(VerboseNumber("12"));           // TwelveDollars
                //Debug.WriteLine(VerboseNumber("123"));          // OneHundredTwentyThreeDollars
                //Debug.WriteLine(VerboseNumber("1234"));         // OneThousandTwoHundredThirtyFourDollars
                //Debug.WriteLine(VerboseNumber("123456789"));    // OneHundredTwentyThreeMillionFourHundredFiftySixThousandSevenHundredEightyNine
                //Debug.WriteLine(VerboseNumber("100000000"));    // OneHundredMillionDollars
                //Debug.WriteLine(VerboseNumber("100000399"));    // OneHundredMillionThreeHundredNinetyNineDollars
                //Debug.WriteLine(VerboseNumber("100000099"));    // OneHundredMillionNinetyNineDollars
                //Debug.WriteLine(VerboseNumber("0"));            // ZeroDollars
                Console.WriteLine(VerboseNumber(line));
            }
    }

    static readonly Dictionary<string, string> ones = new Dictionary<string, string>()
        {
            { "0", ""},
            { "1", "One"},
            { "2", "Two"},
            { "3", "Three"},
            { "4", "Four" },
            { "5", "Five" },
            { "6", "Six"},
            { "7", "Seven"},
            { "8", "Eight" },
            { "9", "Nine"}
        };

    static readonly Dictionary<string, string> tens = new Dictionary<string, string>()
        {
            { "10", "Ten"},
            { "11", "Eleven"},
            { "12", "Twelve"},
            { "13", "Thirteen"},
            { "14", "Fourteen"},
            { "15", "Fifteen"},
            { "16", "Sixteen"},
            { "17", "Seventeen"},
            { "18", "Eighteen"},
            { "19", "Nineteen" }
        };

    static readonly Dictionary<string, string> tensSuper = new Dictionary<string, string>()
        {
            { "0", "" },
            { "2", "Twenty"},
            { "3", "Thirty"},
            { "4", "Forty"},
            { "5", "Fifty"},
            { "6", "Sixty"},
            { "7", "Seventy"},
            { "8", "Eighty"},
            { "9", "Ninety"}

        };


    static string VerboseNumber(string line)
    {
        if (line == "0")
        {
            return "ZeroDollars";
        }
        
        // Given a number, represent as verbose
        // Ex:  123 would be OneHundredTwentyThreeDollars
        StringBuilder verboseNumString = new StringBuilder();

        // handle each set of 3
        List<string> lineSets = GetLineSets(line);
        for (int i = lineSets.Count - 1; i >= 0; i--)
        {
            string handleString = lineSets[i];
            //Debug.WriteLine(handleString);

            char[] handleChars = handleString.ToCharArray();

            if (handleChars.All(c => c == '0'))
            {
                continue;
            }

            verboseNumString.Append(HandleHundreds(handleChars));
            verboseNumString.Append(HandleTeens(handleChars));
            verboseNumString.Append(HandlePrefix(i));
        }

        return $"{verboseNumString}Dollars";
    }

    public static string HandlePrefix(int idx)
    {
        switch (idx)
        {
            case 1:
                {
                    return "Thousand";
                }
            case 2:
                {
                    return "Million";
                }
            case 3:
                {
                    return "Billion";
                }
        }
        return string.Empty;
    }


    public static string HandleTeens(char[] handleChars)
    {
        int charSize = handleChars.Length;
        if (charSize >= 2)
        {
            string teen = $"{handleChars[charSize - 2]}{handleChars[charSize - 1]}"; ;
            if (teen.Substring(0, 1) == "1")
            {
                return tens[teen];
            }
            else
            {
                return $"{tensSuper[teen.Substring(0, 1)]}{ones[teen.Substring(1, 1)]}";
            }
        }
        else
        {
            return $"{ones[handleChars[0].ToString()]}";
        }
    }


    public static string HandleHundreds(char[] handleChars)
    {
        if (handleChars.Length == 3)
        {
            if (handleChars[0] != '0')
            {
                return $"{ones[handleChars[0].ToString()]}Hundred";
            }
        }
        return string.Empty;
    }


    public static List<string> GetLineSets(string line)
    {
        char[] lineChars = line.ToCharArray();
        // handle each set of 3
        List<string> lineSets = new List<string>();

        string currSet = string.Empty;
        for (int i = lineChars.Length - 1; i >= 0; i--)
        {
            currSet += lineChars[i];
            if ((currSet.Length == 3) || (i == 0))
            {
                char[] tmpArr = currSet.ToCharArray();
                Array.Reverse(tmpArr);
                currSet = String.Join("", tmpArr);

                lineSets.Add(currSet);
                currSet = string.Empty;
            }
        }
        return lineSets;
    }
}