한글 url 인코딩

char[] ch = url.AbsoluteUri.ToString().ToCharArray();
StringBuilder sb = new StringBuilder();
Encoding ksc = Encoding.GetEncoding("ks_c_5601-1987");
for (int i = 0; i < ch.Length; i++)
{
  int temp = Convert.ToInt32(ch[i]);
  if (temp < 0 || temp >= 128)
  {
    byte[] bysrc = ksc.GetBytes(ch[i].ToString());
    sb.Append(HttpUtility.UrlEncode(bysrc));
  }
  else
  {
    sb.Append(ch[i]);
  }
}