如何在下面修复这个无效的正则表达式标志

我正在尝试从一个页面中的php脚本中接收文件名，并将其附加到位于单独页面上的javascript函数中。问题是我在错误控制台中收到一个无效的正则表达式标志 w 错误，该错误指出未定义变量："文件图像名称"为以下行：

 var nameimagefile = <?php echo $fileimagename; ?>;

如何修复此错误？

下面是javascript函数（QandATable.php）：

function stopImageUpload(success){
     var nameimagefile = <?php echo $fileimagename; ?>;
      var result = '';
      if (success == 1){
         result = '<span class="msg">The file was uploaded successfully!</span><br/><br/>';
         $('.listImage').append(nameimagefile + '<br/>');
      }
      else {
         result = '<span class="emsg">There was an error during file upload!</span><br/><br/>';
      }
return true;
}

下面是一个单独的页面（imageupload.php）上的php代码，文件名是：

<?php
session_start();
if (isset($_POST['fileimagename'])) {
$_SESSION['fileimagename'] =  $_SESSION[' $_FILES['fileImage']['name']'];
}
if( file_exists("ImageFiles/".$_FILES['fileImage']['name'])) {
    $parts = explode(".",$_FILES['fileImage']['name']);
    $ext = array_pop($parts);
    $base = implode(".",$parts);
    $n = 2;
    while( file_exists("ImageFiles/".$base."_".$n.".".$ext)) $n++;
    $_FILES['fileImage']['name'] = $base."_".$n.".".$ext;
    move_uploaded_file($_FILES["fileImage"]["tmp_name"],
    "ImageFiles/" . $_FILES["fileImage"]["name"]);
    $result = 1;
}
    else
      {
      move_uploaded_file($_FILES["fileImage"]["tmp_name"],
      "ImageFiles/" . $_FILES["fileImage"]["name"]);
      $result = 1;
      }
?>
<script language="javascript" type="text/javascript">window.top.window.stopImageUpload(<?php echo $result;?>);</script>