c# 服务端接入个推指定对象消息推送

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