Question

我目前有一个BeautifulSoup HTML项目列表，我通过以下方法调用获得：

tables = HTML.findAll("table", {"class": "datadisplaytable"})

这只会返回HTML文档中与查询匹配的所有表。这一切都很好，但它返回重复的表（如下面的输出所示）。

我尝试过删除重复项：

tables = list(set(HTML.findAll("table", {"class": "datadisplaytable"})))

它会删除重复项，但不会保留我需要的顺序。

所以我尝试了这个：

holder = [] for item in tables: if item not in holder: holder.append(item)

然而，重复仍然存在。以上方法是否无法处理BeautifulSoup HTML？如果没有，如何删除BeautifulSoup HTML重复项并保留订单？

修改

tables = OrderedDict.fromkeys(HTML.findAll("table", {"class": "datadisplaytable"})).keys()

然后在打印时，它是免费的：

for item in tables: print "\n\n\n" print item

但是，当我尝试打印时执行以下操作，重复的内容又回来了。我疯了吗？

i = 0 while (i < len(tables)-1): print "\n\nitem[i]: \n", tables[i] print "\n\nitem[i+1]: \n", tables[i+1] i += 1

有什么想法吗？

item[i]: <table class="datadisplaytable" summary="This table lists the scheduled meeting times and assigned instructors for this class.."><caption class="captiontext">Scheduled Meeting Times</caption> <tbody><tr> <th class="ddheader" scope="col">Type</th> <th class="ddheader" scope="col">Time</th> <th class="ddheader" scope="col">Days</th> <th class="ddheader" scope="col">Where</th> <th class="ddheader" scope="col">Date Range</th> <th class="ddheader" scope="col">Schedule Type</th> <th class="ddheader" scope="col">Instructors</th> </tr> <tr> <td class="dddefault">Class</td> <td class="dddefault">2:00 pm - 3:15 pm</td> <td class="dddefault">MWF</td> <td class="dddefault">Manchester Hall 241</td> <td class="dddefault">Jan 13, 2015 - May 07, 2015</td> <td class="dddefault">Lecture</td> <td class="dddefault">William H. Turkett (<abbr title="Primary">P</abbr>)<a href="mailto:turketwh@wfu.edu" target="William H. Turkett"><img align="middle" alt="E-mail" border="0" class="headerImg" height="28" hspace="0" name="web_email" src="/wtlgifs/web_email.gif" title="E-mail" vspace="0" width="28"/></a></td> </tr> </tbody></table> item[i+1]: <table class="datadisplaytable" summary="This layout table is used to present the schedule course detail"><caption class="captiontext">Linear Algebra I - MTH 121 - C</caption> <tbody><tr> <th class="ddlabel" colspan="2" scope="row">Associated Term:</th> <td class="dddefault">Spring 2015</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row"><acronym title="Course Reference Number">CRN</acronym>:</th> <td class="dddefault">19765</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Status:</th> <td class="dddefault">**Web Registered** on Nov 05, 2014</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Assigned Instructor:</th> <td class="dddefault"> Jason D. Gaddis<a href="mailto:gaddisjd@wfu.edu" target="Jason D. Gaddis"><img align="middle" alt="E-mail" border="0" class="headerImg" height="28" hspace="0" name="web_email" src="/wtlgifs/web_email.gif" title="E-mail" vspace="0" width="28"/></a> </td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Grade Mode:</th> <td class="dddefault">Standard Letter</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Credits:</th> <td class="dddefault"> 4.000</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Level:</th> <td class="dddefault">Undergraduate</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Campus:</th> <td class="dddefault">Reynolda Campus (UG)</td> </tr> </tbody></table> item[i]: <table class="datadisplaytable" summary="This layout table is used to present the schedule course detail"><caption class="captiontext">Linear Algebra I - MTH 121 - C</caption> <tbody><tr> <th class="ddlabel" colspan="2" scope="row">Associated Term:</th> <td class="dddefault">Spring 2015</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row"><acronym title="Course Reference Number">CRN</acronym>:</th> <td class="dddefault">19765</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Status:</th> <td class="dddefault">**Web Registered** on Nov 05, 2014</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Assigned Instructor:</th> <td class="dddefault"> Jason D. Gaddis<a href="mailto:gaddisjd@wfu.edu" target="Jason D. Gaddis"><img align="middle" alt="E-mail" border="0" class="headerImg" height="28" hspace="0" name="web_email" src="/wtlgifs/web_email.gif" title="E-mail" vspace="0" width="28"/></a> </td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Grade Mode:</th> <td class="dddefault">Standard Letter</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Credits:</th> <td class="dddefault"> 4.000</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Level:</th> <td class="dddefault">Undergraduate</td> </tr> <tr> <th class="ddlabel" colspan="2" scope="row">Campus:</th> <td class="dddefault">Reynolda Campus (UG)</td> </tr> </tbody></table> item[i+1]: <table class="datadisplaytable" summary="This table lists the scheduled meeting times and assigned instructors for this class.."><caption class="captiontext">Scheduled Meeting Times</caption> <tbody><tr> <th class="ddheader" scope="col">Type</th> <th class="ddheader" scope="col">Time</th> <th class="ddheader" scope="col">Days</th> <th class="ddheader" scope="col">Where</th> <th class="ddheader" scope="col">Date Range</th> <th class="ddheader" scope="col">Schedule Type</th> <th class="ddheader" scope="col">Instructors</th> </tr> <tr> <td class="dddefault">Class</td> <td class="dddefault">12:30 pm - 1:45 pm</td> <td class="dddefault">MWF</td> <td class="dddefault">Carswell Hall 101</td> <td class="dddefault">Jan 13, 2015 - May 07, 2015</td> <td class="dddefault">Lecture</td> <td class="dddefault">Jason Dale Gaddis (<abbr title="Primary">P</abbr>)<a href="mailto:gaddisjd@wfu.edu" target="Jason D. Gaddis"><img align="middle" alt="E-mail" border="0" class="headerImg" height="28" hspace="0" name="web_email" src="/wtlgifs/web_email.gif" title="E-mail" vspace="0" width="28"/></a></td> </tr> </tbody></table>

Answer 1

相反，我依赖于桌子上独一无二的东西。例如，在summary属性：

summaries = set()
tables = []

for table in soup.find_all("table", {"class": "datadisplaytable"}):
    summary = table['summary']
    if summary not in summaries:
        summaries.add(summary)
        tables.append(table)

为什么我不能在Python中删除此列表（BeautifulSoup HTML）中的重复项？

1 个答案: