我试图抓取一个格式错误的HTML网页的网站。以一些网页为例：
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta name="keywords" content="physician, doctor, CME, CE, physician job recuiter, Chinese speaking doctors, medical school alumni," />
<meta name="description" content="An online database for physicians who obtained medical degree in China and are practicing in USA. It contains over 6,000 profiles. Email:admin@cmgforum.net for any question." />
<title>
CMG Physician Database - 华人医生数据库
</title>
<link rel="stylesheet" type="text/css" href="default.css" />
<script type="text/javascript">
var _gaq = _gaq || [];
_gaq.push(['_setAccount', 'UA-27283808-3']);
_gaq.push(['_trackPageview']);
(function() {
var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true;
ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js';
var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s);
})();
</script>
<script type="text/javascript">
function validateForm()
{
valid = true;
if ( document.myForm.last.value == "" )
{
alert ( "Last name is required" );
valid = false;
}
else if ( document.myForm.first.value == "" )
{
alert ( "First name is required" );
valid = false;
}
else if ( document.myForm.states.value == "" )
{
alert ( "State is required" );
valid = false;
}
else if ( document.myForm.specialty_id.value == "" )
{
alert ( "Specialty is required" );
valid = false;
}
else if ( document.myForm.gradschool_id.value == "" )
{
alert ( "School is required" );
valid = false;
}
return valid;
}
</script>
<script type="text/javascript">
if (screen.width<800) {
window.location="http://physician.cmgforum.net/m/";
}
</script>
<script language="JavaScript"
type="text/JavaScript">
function changePage(newLoc)
{
nextPage = newLoc.options[newLoc.selectedIndex].value
if (nextPage != "")
{
document.location.href = nextPage
}
}
</script>
</head>
<body>
<div id="outer">
<div id="upbg"></div>
<div id="inner">
<div id="header">
<embed src="flash/cmglogo.swf" width="685" Height="90">
</div>
<div id="menu">
<center>
<ul>
<li><a href="/index.php">Home</a></li>
<li><a href="/search4-d.php">Combo Search</a></li>
<li><a href="/search-d.php">Name</a></li>
<li><a href="/gradsch-d.php">Schools</a></li>
<li><a href="/specialty-d.php">Specialties</a></li>
<li><a href="/loc-spe.php">Local Specialties</a></li>
<li><a href="/location-d.php">States</a></li>
<li><a href="/locations3-d.php">Cities</a></li>
</center>
</div>
<table width="100%">
<tr>
<td width="2%"></td>
<td>
<form method="POST" name="menu" >
<select name="selectedPage"
onChange="changePage(this.form.selectedPage)">
<option value = "" selected>Site Navigation</option>
<option value = "/index.php">Home</option>
<option value = "/facilities.php"> Medical Facilities</option>
<option value = "/stats-d.php">Statistics</option>
<option value = "/contact.php">Contacts</option>
<option value = "/top5.php">The Top5</option>
<option value = "http://blog.cmgforum.net">Blog</option>
<option value = "/links.php">Links</option>
<option value = "/addme.php">Add Me</option>
<option value = "/news.php">News</option>
<option value = "/faq.php">FAQ</option>
<option value = "/pop-d.php">人气</option>
<option value = "/pgy-d.php">PGY</option>
<option value = "/video2-d.php">CMG Videos</option>
<option value = "/url.php">CMG Website</option>
</select>
</form>
</td>
<td>
<script type="text/javascript"><!--
google_ad_client = "ca-pub-6867265085889194";
/* header-links */
google_ad_slot = "9503010667";
google_ad_width = 468;
google_ad_height = 15;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
</td>
</tr></table>
</body>
</html>
<center>
<table><tr>
<td width="5%"></td>
<td>
<center>
<script type="text/javascript"><!--
google_ad_client = "pub-6867265085889194";
/* 468x60, created 8/19/10 */
google_ad_slot = "1699885909";
google_ad_width = 400;
google_ad_height = 60;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
</center>
</td>
<td>
<img src="images/code.jpg" alt="QR Code" height="60" width="60">
</td>
</tr></table>
</center>
<!---
<marquee ALIGN="Top" LOOP="infinite" BGCOLOR="#FFFFFF" DIRECTION="left" HEIGHT=16 WIDTH=640 scrollamount="3" scrolldelay="1"><FONT SIZE="3" FACE="courier" COLOR=blue>
<a href="./bridge.php">第三届健桥医学峰会即将在波士顿召开, 更多的信息请点击这里！</a>
</font></marquee>
--->
<table width="100%" style="text-shadow: 1px 1px 3px #999;"><tr><td width="3%"></td><td width="16%"><a href="loading/specialty/1.php">Allergy & Immunology</a>(20)<br><a href="loading/specialty/2.php">Anesthesiology</a>(595)<br><a href="loading/specialty/3.php">Cardiology</a>(129)<br><a href="loading/specialty/38.php">Dentistry</a>(437)<br><a href="loading/specialty/4.php">Dermatology</a>(29)<br><a href="loading/specialty/5.php">Emergency Medicine</a>(8)<br><a href="loading/specialty/6.php">Endocrinoloy</a>(60)<br><a href="loading/specialty/7.php">Family Practice</a>(434)<br><a href="loading/specialty/8.php">Gastroenterology</a>(88)<br><a href="loading/specialty/9.php">General Surgery</a>(94)<br><a href="loading/specialty/10.php">Geriatric Medicine</a>(48)<br><a href="loading/specialty/11.php">Hem/Onc</a>(295)<br><a href="loading/specialty/12.php">Infectious Disease</a>(12)<br><a href="loading/specialty/13.php">Internal Medicine</a>(1880)<br><a href="loading/specialty/36.php">Medical Genetics</a>(47)<br><br></td><td width="3%"></td><td width="16%"><a href="loading/specialty/14.php">Nephrology</a>(114)<br><a href="loading/specialty/15.php">Neurology</a>(333)<br><a href="loading/specialty/16.php">Neurosurgery</a>(11)<br><a href="loading/specialty/17.php">OB/GYN</a>(83)<br><a href="loading/specialty/18.php">Occupational Med</a>(33)<br><a href="loading/specialty/19.php">Ophthalmology</a>(63)<br><a href="loading/specialty/41.php">Optometry</a>(28)<br><a href="loading/specialty/20.php">Orthopaedics</a>(18)<br><a href="loading/specialty/21.php">Otolaryngology</a>(10)<br><a href="loading/specialty/22.php">Pathology</a>(1235)<br><a href="loading/specialty/23.php">Pediatrics</a>(300)<br><a href="loading/specialty/42.php">Pediatric Hem/Onc</a>(8)<br><a href="loading/specialty/43.php">Pediatric Cardiology</a>(9)<br><a href="loading/specialty/44.php">Pediatric GI</a>(9)<br><a href="loading/specialty/45.php">Pediatric Neurology</a>(13)<br><br></td><td width="3%"></td><td width="17%"><a href="loading/specialty/46.php">Pediatric Endocrinology</a>(10)<br><a href="loading/specialty/47.php">Pediatric Rheumatology</a>(2)<br><a href="loading/specialty/48.php">Pediatric Allergy(Immu)</a>(5)<br><a href="loading/specialty/25.php">Plastic Surgery</a>(5)<br><a href="loading/specialty/26.php">Psychiatry</a>(319)<br><a href="loading/specialty/27.php">Pulmonary Disease</a>(30)<br><a href="loading/specialty/28.php">Radiation Oncology</a>(54)<br><a href="loading/specialty/29.php">Diag Radiology(Nuclear)</a>(156)<br><a href="loading/specialty/24.php">Rehabilitation</a>(216)<br><a href="loading/specialty/40.php">Sports Medicine</a>(2)<br><a href="loading/specialty/30.php">Rheumatology</a>(43)<br><a href="loading/specialty/37.php">Thoracic Surgery</a>(17)<br><a href="loading/specialty/32.php">Urology</a>(12)<br><a href="contact.php">Add New Specialty</a><br><a href="contact.php">Add New Specialty</a><br><br></td><td width="3%"></td><td width="20%"><script type="text/javascript"><!--
google_ad_client = "ca-pub-6867265085889194";
/* spe-120-240 */
google_ad_slot = "2416199460";
google_ad_width = 120;
google_ad_height = 240;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
<br>
</td></tr></table><div id="top5">
<html>
<head>
<link rel="stylesheet" type="text/css" href="default.css" />
</head>
<body>
<center>
<div id="ad">
<script type="text/javascript"><!--
google_ad_client = "pub-6867265085889194";
/* 728x90, created 8/26/10 */
google_ad_slot = "7083487992";
google_ad_width = 715;
//google_ad_width = 728;
google_ad_height = 90;
//-->
</script>
<script type="text/javascript"
src="http://pagead2.googlesyndication.com/pagead/show_ads.js">
</script>
</div>
</center>
</body>
</html>
</div>
<center>
<table border="0" BORDERCOLOR=orange><tr>
<td><div style="padding: 2px; border: 1px red solid;"></div></td>
<td><a href=http://www.wikilips.com/ target="_blank"><img src="http://physician.cmgforum.net/images/wikilips.jpg" border="1" width="160" height="80"></a></td>
<td><a href=http://www.linkedin.com/groups?gid=1648407&trk=myg_ugrp_ovr target="_blank"><img src="http://physician.cmgforum.net/images/MedicalCareer_150x65.gif" border="1" width="170" height="80"></a></td>
<td><img src="http://physician.cmgforum.net/images/scan.JPG" border="0" width="80" height="80">
<img src="http://physician.cmgforum.net/images/qrcode.png" border="0" width="80" height="80">
</td>
</tr></table>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<title>terrafirma1.0 by nodethirtythree</title>
<meta name="keywords" content="" />
<meta name="description" content="" />
<link rel="stylesheet" type="text/css" href="default.css" />
</head>
<body>
<center>
<div id="footer">
© copyright 2007 cmgforum.net. all rights reserved.
Contact: admin@cmgforum.net
</div>
</div>
</div>
</body>
</html>
正如我们从中可以看到的，这里有两个根元素。在这种情况下，Scrapy无法正确解析XPath。任何想法如何处理这个？
答案 0 :(得分：3)
当您遇到格式错误的HTML页面时，请尝试概括您的xpath，因为浏览器和scrapy不会以相同的方式解释页面。在这种情况下，如果要提取表中的链接列表，请尝试这样的xpath：
//tr//td//a[contains(@href,'/specialty/')]