C#.Net 转换人民币大写金额

using System;
using System.Collections.Generic;
using System.Text;
namespace Common
{
   /// <summary>
   /// 转换人民币大小金额。
   /// </summary>
   public class Rmb
   {
      /// <summary>
      /// 转换人民币大小金额
      /// </summary>
      /// <param name="num">金额</param>
      /// <returns>返回大写形式</returns>
      public static string CmycurD(decimal num)
      {
         string str1 = "零壹贰叁肆伍陆柒捌玖"; //0-9所对应的汉字
         string str2 = "万仟佰拾亿仟佰拾万仟佰拾元角分"; //数字位所对应的汉字
         string str3 = ""; //从原num值中取出的值
         string str4 = ""; //数字的字符串形式
         string str5 = ""; //人民币大写金额形式
         int i; //循环变量
         int j; //num的值乘以100的字符串长度
         string ch1 = ""; //数字的汉语读法
         string ch2 = ""; //数字位的汉字读法
         int nzero = 0; //用来计算连续的零值是几个
         int temp; //从原num值中取出的值
         num = Math.Round(Math.Abs(num), 2); //将num取绝对值并四舍五入取2位小数
         str4 = ((long)(num * 100)).ToString(); //将num乘100并转换成字符串形式
         j = str4.Length; //找出最高位
         if (j > 15) { return "溢出"; }
         str2 = str2.Substring(15 - j); //取出对应位数的str2的值。如：200.55,j为5所以str2=佰拾元角分
         //循环取出每一位需要转换的值
         for (i = 0; i < j; i++)
         {
            str3 = str4.Substring(i, 1); //取出需转换的某一位的值
            temp = Convert.ToInt32(str3); //转换为数字
            if (i != (j - 3) && i != (j - 7) && i != (j - 11) && i != (j - 15))
            {
               //当所取位数不为元、万、亿、万亿上的数字时
               if (str3 == "0")
               {
                  ch1 = "";
                  ch2 = "";
                  nzero = nzero + 1;
               }
               else
               {
                  if (str3 != "0" && nzero != 0)
                  {
                     ch1 = "零" + str1.Substring(temp * 1, 1);
                     ch2 = str2.Substring(i, 1);
                     nzero = 0;
                  }
                  else
                  {
                     ch1 = str1.Substring(temp * 1, 1);
                     ch2 = str2.Substring(i, 1);
                     nzero = 0;
                  }
               }
            }
            else
            {
               //该位是万亿，亿，万，元位等关键位
               if (str3 != "0" && nzero != 0)
               {
                  ch1 = "零" + str1.Substring(temp * 1, 1);
                  ch2 = str2.Substring(i, 1);
                  nzero = 0;
               }
               else
               {
                  if (str3 != "0" && nzero == 0)
                  {
                     ch1 = str1.Substring(temp * 1, 1);
                     ch2 = str2.Substring(i, 1);
                     nzero = 0;
                  }
                  else
                  {
                     if (str3 == "0" && nzero >= 3)
                     {
                        ch1 = "";
                        ch2 = "";
                        nzero = nzero + 1;
                     }
                     else
                     {
                        if (j >= 11)
                        {
                           ch1 = "";
                           nzero = nzero + 1;
                        }
                        else
                        {
                           ch1 = "";
                           ch2 = str2.Substring(i, 1);
                           nzero = nzero + 1;
                        }
                     }
                  }
               }
            }
            if (i == (j - 11) || i == (j - 3))
            {
               //如果该位是亿位或元位，则必须写上
               ch2 = str2.Substring(i, 1);
            }
            str5 = str5 + ch1 + ch2;
            if (i == j - 1 && str3 == "0")
            {
               //最后一位（分）为0时，加上“整”
               str5 = str5 + ’整’;
            }
         }
         if (num == 0)
         {
            str5 = "零元整";
         }
         return str5;
      }
      
      /// <summary>
      /// 转换人民币大小金额 (一个重载，将字符串先转换成数字在调用CmycurD)
      /// </summary>
      /// <param name="num">用户输入的金额，字符串形式未转成decimal</param>
      /// <returns></returns>
      public static string CmycurD(string numstr)
      {
         try
         {
            decimal num = Convert.ToDecimal(numstr);
            return CmycurD(num);
         }
         catch
         {
            return "非数字形式！";
         }
      }
   }
}