Solved

Is very easy. Thank You for all helpful reply

Qt Code:
  1. QUrl url("http://192.168.1.109/ask.cgi");
  2. QUrlQuery query;
  3. query.setQuery("json={\"ctrl\":{\"c":\"gd\",\"i\":6}}");
  4. url.setQuery(query);
  5. QNetworkRequest req(url);
  6.  
  7. QNetworkAccessManager test;
  8.  
  9. QEventLoop loop;
  10. connect(&test, SIGNAL(finished(QNetworkReply*)), &loop, SLOT(quit()));
  11. QNetworkReply * reply = test.get(req);
  12. loop.exec();
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Then we get answer