获取汉字拼音首字母

private  string getPinYin(string text)
        {
            char pinyin;
            byte[] array;
             System.Text.StringBuilder sb = new System.Text.StringBuilder(text.Length);
            foreach(char c in text)
            {
                 pinyin = c;
                 array = System.Text.Encoding.Default.GetBytes(new char[]{c});

              if(array.Length == 2)
              {
                  int i = array[0] * 0x100 + array[1];

                  if(i < 0xB0A1) pinyin = c; else
                      if(i < 0xB0C5) pinyin = 'a'; else
                      if(i < 0xB2C1) pinyin = 'b'; else
                      if(i < 0xB4EE) pinyin = 'c'; else
                      if(i < 0xB6EA) pinyin = 'd'; else
                      if(i < 0xB7A2) pinyin = 'e'; else
                      if(i < 0xB8C1) pinyin = 'f'; else
                      if(i < 0xB9FE) pinyin = 'g'; else
                      if(i < 0xBBF7) pinyin = 'h'; else
                      if(i < 0xBFA6) pinyin = 'g'; else
                      if(i < 0xC0AC) pinyin = 'k'; else
                      if(i < 0xC2E8) pinyin = 'l'; else
                      if(i < 0xC4C3) pinyin = 'm'; else
                      if(i < 0xC5B6) pinyin = 'n'; else
                      if(i < 0xC5BE) pinyin = 'o'; else
                      if(i < 0xC6DA) pinyin = 'p'; else
                      if(i < 0xC8BB) pinyin = 'q'; else
                      if(i < 0xC8F6) pinyin = 'r'; else
                      if(i < 0xCBFA) pinyin = 's'; else
                      if(i < 0xCDDA) pinyin = 't'; else
                      if(i < 0xCEF4) pinyin = 'w'; else
                      if(i < 0xD1B9) pinyin = 'x'; else
                      if(i < 0xD4D1) pinyin = 'y'; else
                      if(i < 0xD7FA) pinyin = 'z';
               }

               sb.Append(pinyin);
           }

          return sb.ToString();
         }