是否有任何方法将数据从服务器发送到客户端？

Question

我正在做客户机服务器应用程序(通过带有postgrelsql的浏览器)。我创建了服务器，它运行在一个端口上。如何从服务器到客户端获取数据。客户端：

   req=new HttpRequest();
   req.open('get', 'http://127.0.0.1:8082/');
   var rr=req.send();
   print(rr);

服务器端：

      HttpServer server = await HttpServer.bind('127.0.0.1', 8082);

      await for (HttpRequest request in server) {
      request.response.headers.add("Access-Control-Allow-Origin", "*");
      request.response.headers.add("Access-Control-Allow-Methods",      "POST,GET,DELETE,PUT,OPTIONS");
      request.response.write(await consoledatabaseconnection.someList());
      handleRequest(request);
      request.response.close();
    }
   void handleRequest(HttpRequest request) {
  try {
    if (request.method == 'GET') {
      print('request get');

      request.response.write('data form server');

    } else {
      print('request others');
    }
  } catch (e) {
    print('Exception in handleRequest: $e');
  }
  print('Request handled.');
}

在服务器端，如何返回数据。

Answer 1

服务器端代码

main(List<String> arguments) async {
  HttpServer.bind('localhost', 8085).then((server) {
    server.listen((HttpRequest request) {
      request.response.headers.add("Access-Control-Allow-Origin", "*");
      request.response.headers
          .add("Access-Control-Allow-Methods", "POST,GET,DELETE,PUT,OPTIONS");
      request.response.headers.add('Access-Control-Allow-Headers',
          'Origin, X-Requested-With, Content-Type, Accept,application/x-www-form-urlencoded');

      if (request.method == "POST") {
        List<int> dataBody = new List<int>();
        request.listen(dataBody.addAll, onDone: () async {
          query_dy = new String.fromCharCodes(dataBody);
          request.response.write(await databaseconnection('your response code here'));
          request.response.close();
        });
      }
    });
  });
}

客户端代码req =新的HttpRequest()；

req.open('post', 'http://localhost:8085');

req.setRequestHeader('Content-type', 'application/x-www-form-urlencoded');

req.send('{"username": "$username","password": "$password"}');

req.onReadyStateChange.listen((_) {
  if (req.readyState == HttpRequest.DONE &&
      (req.status == 200 || req.status == 0)) {
        //you can get response form server here
    String responsefrmserver = req.responseText;

    } 
  }
});