Php 在codename one中使用webservices时如何解析null

我在php中调用数据库中的数据，并使用Webservices将数据传递给codename one。如果我将URL指向JSON文件，我可以获取记录，但当我将其更改为php并使用JSON对页面进行编码时，我得到的是空值

在Codename one中使用Webservices时，如何解析空结果

这是我在代码名one中调用的php代码

<?php 
/* require the user as the parameter */
//http://localhost:8080/sample1/webservice1.php?user=1
if(isset($_GET['user']) && intval($_GET['user'])) {
    /*soak in the passed variable or set our own*/
    //$number_of_posts = isset($_GET['num']) ? intval($_GET['num']) : 10; //10 is the default
    $format = strtolower($_GET['format']) == 'json' ? 'json' : 'xml'; //xml is  the default
    //$user_id = intval($_GET['user']); //no default

    /* connect to the db */
    $link = mysql_connect('localhost','root','') or die('Cannot connect to the DB');
    mysql_select_db('test',$link) or die('Cannot select the DB');

    /* grab the posts from the db */
    //$query = "SELECT post_title, guid FROM wp_posts WHERE post_author =     $user_id AND post_status = 'publish' ORDER BY ID DESC LIMIT $number_of_posts";
    $query = "SELECT * FROM bugs";
    $result = mysql_query($query,$link) or die('Errant query:  '.$query);

    /* create one master array of the records */
    $posts = array();
    if(mysql_num_rows($result)) {
        while($post = mysql_fetch_assoc($result)) {
            $posts[] = array('respons'=>$post);
        }
    }

    /* output in necessary format */
    if($format == 'json') {
        // header('Content-type: application/json');
        echo json_encode(array('respons'=>$posts));
    }


    /* disconnect from the db */
    @mysql_close($link);
}

private static final String URL = "http://localhost/webpin/webservice1.php?user=1&format=json";
showpix.addActionListener((e)->{
    ConnectionRequest req = new ConnectionRequest() {
        @Override
        protected void handleException(Exception ex) {
            //handle error
        }
    };
    req.setUrl(URL);
    req.setPost(true);
    req.setHttpMethod("GET"); //Change to GET if necessary
    req.setDuplicateSupported(true);
    req.addArgument("user", mypin.getText());
    //req.addArgument("argumentToSendThroughPostOrGet2", "value2");
    NetworkManager.getInstance().addToQueueAndWait(req);

    if (req.getResponseCode() == 200) {
        Map<String, Object> out = new HashMap<>();
        Display.getInstance().invokeAndBlock(() -> {
            JSONParser p = new JSONParser();
            try (InputStreamReader r = new InputStreamReader(new ByteArrayInputStream(req.getResponseData()))) {
                out.putAll(p.parseJSON(r));
            } catch (IOException ex) {
                //handle error
            }
        });
        if (!out.isEmpty()) {
            List<Map<String, Object>> responses = (List<Map<String, Object>>) out.get("respons");
            for (Object response : responses) {
                Map res = (Map) response;
                //Object hk =  res.get("id");
                System.out.println(res.get("id"));
                //if(hk.equals("I was returned")){
                     Dialog.show("ok",res.get("id") + "", "ok", "ok");
                //}
                //System.out.println(res.get("key"));
            }
        } else {
            //handle error
        }
    } else {
        //handle error
    }
    //req.setPost(false);
    NetworkManager.getInstance().addToQueueAndWait(req);   
});

代码如下：

      showpix.addActionListener((e)->{
      ConnectionRequest req = new ConnectionRequest() {
      @Override
      protected void handleException(Exception ex) {
    //handle error
    }
   };
   req.setUrl(DESTINATION_URL);
   req.setPost(true);
   req.setHttpMethod("GET"); //Change to GET if necessary
   req.setDuplicateSupported(true);
   //req.addArgument("user", mypin.getText());

   req.addArgument("user", mypin.getText());
   req.addArgument("format", "json");
   req.setPost(false);
    NetworkManager.getInstance().addToQueueAndWait(req);   

    if (req.getResponseCode() == 200) {
   Map<String, Object> out = new HashMap<>();
   Display.getInstance().invokeAndBlock(() -> {
    JSONParser p = new JSONParser();
      try (InputStreamReader r = new InputStreamReader(new           ByteArrayInputStream(req.getResponseData()))) {
        out.putAll(p.parseJSON(r));
       } catch (IOException ex) {
        //handle error
        }
      });


        if (!out.isEmpty()) {
        List<Map<String, Object>> responses = (List<Map<String, Object>>) out.get("response");
          for (Object response : responses) {
             Map res = (Map) response;

         // Object hk =  res.get("id");
           System.out.println(res.get("id"));
        // if(hk.equals("I was returned")){
    //     Dialog.show("ok",res.get("pin")+ "", "ok", "ok");


  //    }

        System.out.println(res.get("id"));



         }
         } else {
        //handle error
          }
          } else {
            //handle error
           }


               });

---

我注意到的第一件事是您调用了

NetworkManager.getInstance（）.addToQueueAndWait（req）两次

第二件事是，您应该更改
req.setPost（true）至<代码>请求设置柱（假）如果您在php中使用$\u GET方法

第三，从您的URL中删除“？”和之后的所有内容，无论您想传递什么，都应通过以下方式添加：

网址：

private static final String URL = "http://localhost/webpin/webservice1.php";

req.addArgument("format", "json");
req.addArgument("user", mypin.getText());

参数：

private static final String URL = "http://localhost/webpin/webservice1.php";

req.addArgument("format", "json");
req.addArgument("user", mypin.getText());

在php端，在浏览器中运行代码以确保代码中没有错误。确保取消对
标题的注释。请参阅下面对代码的微小更改：

$posts = array();
$row = array();
if(mysql_num_rows($result)) {
    while($post = mysql_fetch_assoc($result)) {
        $posts["response"][] = $post;
    }
    $row = array("respons" => $posts["response"], "code" => 200, "message" => "success");
} else {
    $row = array("code" => 101, "message" => "No data was returned");
}

/* output in necessary format */
if($format == 'json') {
    header('Content-type: application/json');
    echo json_encode($row, JSON_PRETTY_PRINT);
}

记住把我对你的另一个问题的回答标记为答案。请记住，我仍然面临这个代码的挑战。我已经添加了详细信息，您不应该调用
req.addArgument（“key”、“value”）req.setHttpMethod（“POST”）之前的代码>。MyApplication.java的第293行是什么？第293行是：req.setPost（false）；是否有调用
req.addArgument（“key”、“value”）在第293行之前？如果有，请将其移到该线下方。