个推消息推送主要步骤：1.获取鉴权token 2.发送推送消息

1.获取鉴权token(会过期，需要间隔时间获取一次):

tokenUrl = "https://restapi.getui.com/v2/" + appId + "/auth";

        private string GetToken()

        {

            long nowTime ;    //当前的时间戳 毫秒级

            string sign = appKey + nowTime + masterSecret;

            string sha256Sign = SHA256EncryptString(sign);  //用sha256加密

            string postParam = "{\"sign\":\"" + sha256Sign + "\",\"timestamp\":\"" + nowTime + "\",\"appkey\":\""+ appKey + "\"}";   //json格式的post参数 appkey masterSecret appid 申请应用后会有

            return HttpRequestPost(tokenUrl, postParam);

        }

        private string HttpRequestPost(string Url, string Param)

        {

            string result = string.Empty;

            try

            {

                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);

                request.Timeout = Timeout;

                request.ContentType = "application/json;charset=utf-8";

                request.ReadWriteTimeout = Timeout;

                request.Proxy = null;

                request.ServicePoint.Expect100Continue = false;

                request.KeepAlive = false;

                request.ServicePoint.ConnectionLimit = 1000;    //对象最大连接数

                request.Method = "POST";

                byte[] data = Encoding.UTF8.GetBytes(Param);

                using (Stream requestStream = request.GetRequestStream())

                {

                    using (StreamWriter swrite = new StreamWriter(requestStream))

                    {

                        swrite.Write(data);

                    }

                }

                HttpWebResponse wbResponse = (HttpWebResponse)request.GetResponse();

                using (Stream responseStream = wbResponse.GetResponseStream())

                {

                    using (StreamReader sread = new StreamReader(responseStream))

                    {

                        result = sread.ReadToEnd();

                    }

                }

            }

            catch (Exception ex)

            {

                 Console.WriteLine("GeTuiMsgTask.HttpRequestPost post failed url={0} ex={1}", Url, ex);

            }

            return result;

        }

        private string SHA256EncryptString(string data)

        {

            byte[] bytes = Encoding.UTF8.GetBytes(data);

            byte[] hash = SHA256Managed.Create().ComputeHash(bytes);

            StringBuilder builder = new StringBuilder();

            for (int i = 0; i < hash.Length; i++)

            {

                builder.Append(hash[i].ToString("x2"));

            }

            return builder.ToString();

        }

2. 发送推送消息：必要参数

string cid 客户端给过来的clientid（目标用户）

string requestId 请求唯一标识号，10-32位之间；如果request_id重复，会导致消息丢失

string title, 推送消息标题

string content 推送内容

pushUrl = "https://restapi.getui.com/v2/" + appId + "/push/single/cid"; 推送url


 　　　　private void SendMsgNotification(object o)

        {

            MsgTaskItem item = (MsgTaskItem)o;

            string postParam = "{\"request_id\":\"" + item.RequestId + "\",\"audience\":{\"cid\":[\"" + item.Cid + "\"]}," +

                "\"push_message\":{\"notification\":{\"title\":\"" + item.Title + "\",\"body\":\"" + item.Content + "\",\"click_type\":\"none\",\"url\":\"\"}}}";

            string result = HttpRequestPost(pushUrl, postParam);   //返回结果成功也是json格式字符串

        }

更具体的查看官方文档：https://docs.getui.com/getui/server/rest_v2/push/
在线http接口测试网站：https://www.sojson.com/http/test.html