jQuery数据表-搜索和页面不起作用

Question

我按照文档中的说明使用了数据表，但“搜索”无法正常工作，页面卡在了第1页上。

所有记录均显示。服务器端的响应似乎是正确的。

HTML

<link rel="stylesheet" type="text/css" href="bootstrap4/DataTables/datatables.css">
<script type="text/javascript" charset="utf8" src="bootstrap4/DataTables/datatables.js"></script>

<a onClick="openList();">Open Dialog</a>
<table id="itwr">
  <thead>
    <tr>
      <th class="itwr_no">IT Work No.</th>
      <th>Summary</th>
      <th>Requested By</th>
      <th>Req. Date</th>
    </tr>
  </thead>
  <tbody>
  </tbody>
</table>

JS

function openList(){
  $("#itwr").dataTable({
    "bServerSide": true,
    "lengthChange": false,
    "retrieve":true,
    "sAjaxSource": "dashboard.php?action=getITWR",
    "aoColumns": [{
      "mData": "itwr_no"
    },{
      "mData": "itwr_summary","width": "22%", "bSortable": true
    },{
      "mData": "itwr_requestedby"
    },{
      "mData": "request_date"
    }]
  });
}

PHP

$jsonRes["iTotalRecords"]=$i;
$jsonRes["iTotalDisplayRecords"]=10;
$jsonRes["sEcho"]= 1;
$jsonRes["aaData"]=$data;
echo json_encode($jsonRes);