string str = "20070111";
            SHA1 sha1 = new SHA1CryptoServiceProvider();
            byte[] bytes_sha1_in = UTF8Encoding.Default.GetBytes(str);
            byte[] bytes_sha1_out = sha1.ComputeHash(bytes_sha1_in);
            string str_sha1_out = BitConverter.ToString(bytes_sha1_out);
            MessageBox.Show(str_sha1_out);