如果单击网格中的相应按钮，如何在模式对话框中打开上载的文件？

Question

当我点击每行的相应按钮时，所有其他按钮点击的iframe中会显示最新上传的pdf文件。 Iframe内容似乎没有刷新。这是我的代码：

<a  onclick="opendoc(id)" data-id="<?php echo $value["doc_id"]; ?>"class="button blue" id="<?php echo $value["doc_id"]; ?>" data-toggle="modal" data-target="#myModal">


<!-- Modal -->
<div class="modal fade bd-example-modal-lg" id="myModal" tabindex="-1" role="dialog" aria-labelledby="myModalLabel" aria-hidden="true">
  <div class="modal-dialog modal-lg">
    <div class="modal-content">
      <div class="modal-header">
        <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
        <h4 class="modal-title" id="myModalLabel">View File</h4> 
      </div>
      <div class="modal-body">
        <div style="text-align: center;">
        <iframe src="download.php?mode=view&id=<?php echo $value["document"];?>" id="myframe" style="border:5px solid grey;" width="800" height="600"></iframe>
</div>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
      </div>
    </div>
  </div>
</div>

以下是javascript代码：

function opendoc(id)
  {
  var omyFrame = document.getElementById("myframe");

omyFrame.style.display="block";
alert(id);

  }

并将文件显示到iframe， download.php如下

<?php
    $file = './uploads/'.$_GET['id'];
    $title=$_GET['id'];





    header("Pragma: public");
   // header('Content-disposition: attachment; filename='.$title);
    //header('Content-disposition: inline');
    header('Content-Disposition: inline; filename="' . $file . '"');
    header('Content-type: application/vnd.openxmlformats-officedocument.word');
    header('Content-type: image/jpeg');
      header('Content-Type: application/octet-stream');
    //header('Content-type: text/plain');
    header('Content-type: application/pdf');   
    header('Content-Transfer-Encoding: binary');
    header('Content-Length: ' . filesize($file));

    ob_clean();
    flush();


        readfile($file);

    ?>