C# json 字符串转码Unicode

public string StringToUnicode(string s)
        {
            char[] charbuffers = s.ToCharArray();
            byte[] buffer;
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < charbuffers.Length; i++)
            {
                buffer = System.Text.Encoding.Unicode.GetBytes(charbuffers[i].ToString());
                sb.Append(String.Format("\\u{0:X2}{1:X2}", buffer[1], buffer[0]));
            }
            return sb.ToString();
        }