RestSharp Body Raw， https 支持

    public static IRestResponse RestPost(string url, object bodyRawObj) {
        var request = new RestRequest(Method.POST);
        request.Timeout = 30000;
        request.RequestFormat = DataFormat.Json;
        request.AddBody(bodyRawObj); //Body Raw Format
        ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls |
                                                SecurityProtocolType.Tls11 |
                                                SecurityProtocolType.Tls12 | 
                                                SecurityProtocolType.Ssl3;
        var resp = new RestClient(url).Post(request);
        return resp;
    }