using System;

namespace ConsoleApp
{
/// <summary>
/// 本类实现阿拉伯数字到大写中文的转换
/// 该类没有对非法数字进行判别
/// 请调用NumToChn方法
/// </summary>
public class NumFormat
{
  public NumFormat()
  {
   //
   // TODO: 在此处添加构造函数逻辑
   //
  }
  
  // 转换数字
  private char ToNum(char x)
  {
   string strChnNames="零一二三四五六七八九";
   string strNumNames="0123456789";
   return strChnNames[strNumNames.IndexOf(x)];
  }
  
  // 转换万以下整数
  private string ChangeInt(string x)
  {
   string[] strArrayLevelNames=new string[4] {"","十","百","千"};
   string ret = "";
   int i;
   for (i=x.Length-1;i>=0;i--)
    if (x[i] == '0')
     ret = ToNum(x[i]) + ret;
    else
     ret = ToNum(x[i]) + strArrayLevelNames[x.Length-1-i] + ret;
   while ((i=ret.IndexOf("零零"))!=-1)
    ret=ret.Remove(i, 1);
   if (ret[ret.Length-1]=='零' && ret.Length>1)
    ret=ret.Remove(ret.Length-1,1);
   if (ret.Length>=2 && ret.Substring(0,2)=="一十")
    ret=ret.Remove(0,1);
   return ret;
  }

  // 转换整数
  private string ToInt(string x)
  {
   int len = x.Length;
   string ret,temp;
   if (len<=4)
    ret = ChangeInt(x);
   else if (len<=8)
   {
    ret = ChangeInt(x.Substring(0,len-4)) + "万";
    temp = ChangeInt(x.Substring(len-4,4));
    if (temp.IndexOf("千")==-1 && temp!="")
     ret += "零" + temp;
    else
     ret += temp;
   }
   else
   {
    ret=ChangeInt(x.Substring(0,len-8)) + "亿";
    temp=ChangeInt(x.Substring(len-8,4));
    if (temp.IndexOf("千")==-1 && temp!="")
     ret += "零" + temp;
    else
     ret += temp;
    ret += "万";
    temp = ChangeInt(x.Substring(len-4,4));
    if (temp.IndexOf("千")==-1 && temp!="")
     ret += "零" + temp;
    else
     ret += temp;
   }
   int i;
   if ((i=ret.IndexOf("零万"))!=-1)
    ret = ret.Remove(i+1,1);
   while ((i=ret.IndexOf("零零"))!=-1)
    ret = ret.Remove(i,1);
   if (ret[ret.Length-1]=='零' && ret.Length>1)
    ret = ret.Remove(ret.Length-1,1);
   return ret;
  }

  private string ToDecimal(string x)
  {
   string ret="";
   for (int i=0;i<x.Length;i++)
    ret += ToNum(x[i]);
   return ret;
  }

  public string NumToChn(string x)
  {
   if (x.Length==0)
    return "";
   string ret="";
   if (x[0]=='-')
   {
    ret="负";
    x=x.Remove(0,1);
   }
   if (x[0].ToString()==".")
    x="0"+x;
   if (x[x.Length-1].ToString()==".")
    x=x.Remove(x.Length-1,1);
   if (x.IndexOf(".")>-1)
    ret += ToInt(x.Substring(0,x.IndexOf(".")))+"点"+ToDecimal(x.Substring(x.IndexOf(".")+1));
   else
    ret += ToInt(x);
   return ret;
  }
}
}



测试工程

using System;

namespace ConsoleApp
{
class MainClass
{
  static void Main(string[] args)
  {
   /*
   System.Console.WriteLine("Hello, The World!");
   
   System.Console.WriteLine("My Love!");

   ClassTest ct = new ClassTest();
            System.Console.WriteLine(ct.Get_Str());
   */
   
   /*
   // 重载运算符
            MyVector v1 = new MyVector(5, 12);
   MyVector v2 = new MyVector(4, 3);
   MyVector v3 = new MyVector();
   v3 = v1 + v2;
   System.Console.WriteLine("{0}测试一下", v3.Length);
   */

   // 转换成大写数字
   NumFormat nf = new NumFormat();
   string x;
   while (true)
   {
    Console.Write("X=");
    x = Console.ReadLine();
    if (x == "") break;
    Console.WriteLine("{0}={1}", x, nf.NumToChn(x));
   }
  }
}
}