Question

用var_dump回显解码数组时遇到问题。单击每一行的按钮后，一个唯一的xmlhttprequest，然后执行一个ajax调用理论，但在实践中，ajax不应该如何工作。如果我在加载页面后查看源代码，所有看起来都很好，并且对于每一行，都会创建一个唯一的xmlhttprequest和ajax请求

当我运行var_dump($jsonArray)时，我得到NULL导致此行为的原因是什么？

我的javascript：

    $("#button1").click( function() {
               <?php foreach ($results as $key => $row): ?>    
                var currentdate = new Date(); 
             if (window.XMLHttpRequest) {
                    // code for IE7+, Firefox, Chrome, Opera, Safari
                    xmlhttp = new XMLHttpRequest();
                } else {
                    // code for IE6, IE5
                    xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
                }
                xmlhttp.onreadystatechange = function() {
                    if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
                        $.ajax({
    url: "insertvolume.php",
    type: "POST",
    data: {myData: xmlhttp.responseText},
    contentType: "application/json",
    success: function(output) {
                      //alert(output);
                  }
});
                    }
                };

               xmlhttp.open("GET","http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20IN%20(%22<?php echo $row["symbol"]; ?>%22)&format=json&env=http://datatables.org/alltables.env",true);
                 //xmlhttp.open("GET","http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20IN%20(%22LLNW%22,%22AAPL%22)&format=json&env=http://datatables.org/alltables.env",true);
                xmlhttp.send();

              <?php endforeach; ?> 
         });

一块php：

$jsonString = $_POST['myData'];
$jsonarray = json_decode($jsonString[0]['query']);
var_dump($jsonArray);

div元素中xmlhttprequest的json数组：

<div id="output">{"query":{"count":1,"created":"2016-02-15T16:03:29Z","lang":"de-DE","results":{"quote":{"symbol":"ZN","Ask":"2.05","AverageDailyVolume":"42000"}}}}</div>

Answer 1

$jsonString变量中有一个json字符串，但不是数组。
解码该字符串后，您将收到stdClass的对象请看下面的代码：

// your json string (the same as in $_POST['mydata'])
$json_str = '{"query":{"count":1,"created":"2016-02-15T16:03:29Z","lang":"de-DE","results":{"quote":{"symbol":"ZN","Ask":"2.05","AverageDailyVolume":"42000"}}}}';

$obj = json_decode($json_str);
var_dump($obj->query->results);

// the output
object(stdClass)[15]
  public 'quote' => 
    object(stdClass)[16]
      public 'symbol' => string 'ZN' (length=2)
      public 'Ask' => string '2.05' (length=4)
      public 'AverageDailyVolume' => string '42000' (length=5)

Answer 2

除罗马的答案外：

// your json string (the same as in $_POST['mydata'])
$json_str = '{"query":{"count":1,"created":"2016-02-15T16:03:29Z","lang":"de-DE","results":{"quote":{"symbol":"ZN","Ask":"2.05","AverageDailyVolume":"42000"}}}}';

$results = json_decode($json_str);
$results = $results->query->results;

<?php foreach ($results as $key => $row): 
         echo $row->symbol;
endforeach; ?>

您必须使用$ row-＆gt;符号，因为它是对象，而不是数组。

foreach循环中的XMLHttpRequests和ajax

2 个答案: