PHP url检索提交的数据失败 - PHP url failed to retrieve submitted data

我有一个表单，我已经创建了一个url来获取数据。它是抓取数据正确，但当我击中url它显示我{"error":"null"}。如何获得提交的值?我无法显示web服务。我正试图创建一个网络服务。在提交表单后，当我试图用值

击中url时

http://www.apnapaisa.com/ajaxv2/getCompareResults.html?rateType=Both&occupation=Salaried&offeringTypeId=31&city=79&loanAmt=500000&q=&age=27

返回{"error":"null"}错误

    <?php
    if($_POST["occupation"] == '1'){
        $occupation = 'Salaried';
    }
    else{
        $occupation = 'Self+Employed';
    }
    $url = 'http://www.apnapaisa.com/ajaxv2/getCompareResults.html?productId='.$_POST["product_id"].'&rateType=Floating&occupation='.$occupation.'&monthlyIncome='.$_POST["dincome"].'&offeringTypeId='.$_POST["offeringID"].'&city='.$_POST["city"].'&monthlyIncomeSingle='.$_POST["dincome"].'&loanAmt='.$_POST["loan"].'&q='.$_POST["q"].'&age='.$_POST["age"].'&tenure='.$_POST["tenure"];
    echo $url;
    //  Initiate curl
    $ch = curl_init();
    // Disable SSL verification
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    // Will return the response, if false it print the response
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    // Set the url
    curl_setopt($ch, CURLOPT_URL,$url);
    // Execute
    $result=curl_exec($ch);
    // Closing
    curl_close($ch);
    $json = json_decode($result, true);
    //print_r($json); 
    //echo $json['resultList']['interestRateMin'];
    $json_array = $json['resultList'];
    //print_r($json_array);
    ?>
      <?php 
          if (is_array($value)) {
        foreach ($json['resultList'] as $key=>$value) {
            if($json["resultList"][$key]["interestRateMin"] == $json["resultList"][$key]["interestRateMax"]){
                $interest = $json["resultList"][$key]["interestRateMin"];
            }
            else{
                $interest = $json["resultList"][$key]["interestRateMin"].' - '.$json["resultList"][$key]["interestRateMax"];
            }
                echo '  
                  <div class="bank-rates">
      <ul>
   <li><div class="innr-spl" style="padding: 5px 0;"><span style="display:block;"><img src="'.$json["resultList"][$key]["imageUrl"].'"></span></div></li>
   <li><div class="innr-spl2">'.$json["resultList"][$key]["interestRateMin"].'%'.'</div></li>
   <li><div class="innr-spl2">60</div> </li>
   <li class="hide"><div class="innr-spl3 view-detail1" id="'.$key.'"><i class="fa fa-chevron-circle-down" aria-hidden="true"></i>View Datails</div> </li>
   <li><div class="apply-now innr-spl"><a href="#" type="button" role="button" target="_blank" class="btn-apply">Apply Now</a></div></li>
      </ul>
      <div style="clear:both"></div>
      <div id="ban_'.$key.'"> 
      <ul class="details" id="details1">
        <li><i class="fa fa-thumbs-o-up" aria-hidden="true"></i> Maximum Loan Amount : '.$json["resultList"][$key]["loanAmt"].'</li>
        <li><i class="fa fa-thumbs-o-up" aria-hidden="true"></i> Max Tenure (In Years) : '.$json["resultList"][$key]["tenure"].'</li>
        <li><i class="fa fa-thumbs-o-up" aria-hidden="true"></i> Interest Rate Type : '.$json["resultList"][$key]["rateType"].'</li>
      </ul>
      </div>
    </div>

                ';
                $i++;
        }
}
    ?>

// $postData = xxx; //add your data
   foreach($_POST as $k => $v) 
   { 
      $postData .= $k . '='.$v.'&'; 
   }
   $postData = rtrim($postData, '&');
$url ="http://www.apnapaisa.com/ajaxv2/getCompareResults.html"
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
curl_setopt($ch, CURLOPT_HEADER, TRUE); // Includes the header in the output
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS,$postData);
$output=curl_exec($ch);