title: How to send push notification to more then 1000 user through GCM
body: <p>I'm using asp.net c# to send push notifications to users through GCM. This is my code to send notification.</p>
  
  <pre><code>string RegArr = string.Empty;
  RegArr = string.Join("\",\"", RegistrationID);      // (RegistrationID) is Array of endpoints
  
  string message = "some test message";
  string tickerText = "example test GCM";
  string contentTitle = "content title GCM";
   postData =
  "{ \"registration_ids\": [ \"" + RegArr + "\" ], " +
  "\"data\": {\"tickerText\":\"" + tickerText + "\", " +
  "\"contentTitle\":\"" + contentTitle + "\", " +
  "\"message\": \"" + message + "\"}}";
  
  string response = SendGCMNotification("Api key", postData);
  </code></pre>
  
  <p>SendGCMNotification Function:-</p>
  
  <pre><code>private string SendGCMNotification(string apiKey, string postData, string postDataContentType = "application/json")
      {
  
          byte[] byteArray = Encoding.UTF8.GetBytes(postData);
  
          //  CREATE REQUEST
          HttpWebRequest Request = (HttpWebRequest)WebRequest.Create("https://android.googleapis.com/gcm/send");
          Request.Method = "POST";
          Request.KeepAlive = false;
          Request.ContentType = postDataContentType;
          Request.Headers.Add(string.Format("Authorization: key={0}", apiKey));
          Request.ContentLength = byteArray.Length;
  
          Stream dataStream = Request.GetRequestStream();
          dataStream.Write(byteArray, 0, byteArray.Length);
          dataStream.Close();
          //
          //  SEND MESSAGE
          try
          {
              WebResponse Response = Request.GetResponse();
              HttpStatusCode ResponseCode = ((HttpWebResponse)Response).StatusCode;
              if (ResponseCode.Equals(HttpStatusCode.Unauthorized) || ResponseCode.Equals(HttpStatusCode.Forbidden))
              {
                  var text = "Unauthorized - need new token";
              }
              else if (!ResponseCode.Equals(HttpStatusCode.OK))
              {
                  var text = "Response from web service isn't OK";
              }
              StreamReader Reader = new StreamReader(Response.GetResponseStream());
              string responseLine = Reader.ReadToEnd();
              Reader.Close();
  
              return responseLine;
          }
          catch (Exception ex)
          {
              throw ex;
          }
          return "error";
      }
  </code></pre>
  
  <p>It is working properly and notification delivered properly to 1000 users.But now i have more then 1000 users and i have to send notifications to them all,but in gcm documentation it is specified that we can pass 1000 registrations ids at one time.what can i do to send notification to all user?Any help will be appriciated</p>
  
  <p><a href="https://i.stack.imgur.com/q9Dfo.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/q9Dfo.png" alt="enter image description here"></a></p>