public async Task GetItemsFromListByCaseNumber(string Case_Number)
            {
                byte[] responseString;

                try
                {
                    string requestUrl = "/Case Document/items?expand=fields&filter=fields/CaseNumber eq '" + Case_Number + "'";
                    await PostRequestToSharepoint(requestUrl, HttpMethod.Get);
                }
                catch (Exception ex)
                {
                }

            }

public async Task<Dictionary<String, JsonValue>> PostRequestToSharepoint(string url, HttpMethod method)
        {
            byte[] responseString;
            Dictionary<String, JsonValue> list = new Dictionary<String, JsonValue>();
            try
            {
                string accessToken = await new ServiceAPIConnection().GetToken();
                string requestUrl = sharepointURL + "/sites/albaabtech.sharepoint.com:/sites/hha:/lists/Case Document/items?$select=AppointmentID&$filter=AppointmentID eq 'APPXID100000745'";

               // string requestUrl = sharepointURL + "/sites/albaabtech.sharepoint.com:/sites/hha:/lists" + url;

                HttpClient client = new HttpClient();

                HttpRequestMessage message = new HttpRequestMessage(method, requestUrl);
                message.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
                message.Headers.Authorization = new AuthenticationHeaderValue("Bearer",accessToken);
                HttpResponseMessage response = await client.SendAsync(message);
                if (response.IsSuccessStatusCode)
                {
                    responseString = await response.Content.ReadAsByteArrayAsync();

                    //Dictionary<String, IJsonValue> listDict = new Dictionary<string, IJsonValue>();
                    //ParseJson(JsonObject.Parse(Encoding.UTF8.GetString(responseString, 0, responseString.Length)), listDict); //parse the json payload we got back

                    //JsonArray lists = listDict["value"].GetArray(); // the "value" json structure contains the list metadata

                    //if (lists.Count > 0)
                    //{
                    //    foreach (IJsonValue item in lists)
                    //    {
                    //        try
                    //        {
                    //            ParseJson(item.GetObject(), list);
                    //        }
                    //        catch
                    //        {
                    //            Do no crash the app if we cannot parse the payload for a list
                    //        }
                    //    }
                    //}
                }
                //else
                //   responseString = "Error in response";
            }
            catch (Exception ex)
            {
               // responseString = "Exception: " + ex.Message;
            }

            return list;

        }