C#将数字转换为单词

using System;
using System.Collections.Generic;
using System.Text;

namespace Demo {
   class MyApplication {
      static void Main(string[] args) {

         int val, next, num_digits;
         int[] a = new int[10];

         // words for every digits from 0 to 9
         string[] digits_words = {
            zero,
            one,
            two,
            three,
            four,
            five,
            six,
            seven,
            eight,
            nine
         };

         // number to be converted into words
         val = 4677;
         Console.WriteLine(Number:  + val);
         Console.Write(Number (words): );

         next = 0;
         num_digits = 0;

         do {
            next = val % 10;
            a[num_digits] = next;
            num_digits++;
            val = val / 10;
         } while (val > 0);

         num_digits--;

         for (; num_digits >= 0; num_digits--)
         Console.Write(digits_words[a[num_digits]] +  );
         Console.ReadLine();
      }
   }
}