python-使用lxml处理请求中的html. TypeError：无法腌制_ElementUnicodeResult对象

我正在尝试在页面上的特定xpath上找到数据.我可以通过请求到达页面.通过使用r.text将源代码打印到屏幕上,并将显示的文本与我要查找的文本进行比较,我已经验证我处于正确的页面.

r.text返回的字符串很难提取我想要的信息.我被告知lxml是通过xpath搜索信息的一种方式.不幸的是,我收到类型错误.

from lxml import html
import requests

payload = {'login_pass': 'password', 'login_user': 'username','submit':'go'}
r = requests.get("website", params=payload)

print r.encoding
tree = html.fromstring(r.text)
print tree
print tree.text_content()

退货

UTF-8
<Element html at 0x10dab8d08>

Traceback (most recent call last):
  File "/Users/Me/Documents/PYTHON/GetImageAsPdf/ImageToPDF_requests_beta.py", line 11, in <module>
    print tree.text_content()
  File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/idlelib/PyShell.py", line 1343, in write
    return self.shell.write(s, self.tags)
  File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/idlelib/rpc.py", line 595, in __call__
    value = self.sockio.remotecall(self.oid, self.name, args, kwargs)
  File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/idlelib/rpc.py", line 210, in remotecall
    seq = self.asynccall(oid, methodname, args, kwargs)
  File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/idlelib/rpc.py", line 225, in asynccall
    self.putmessage((seq, request))
  File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/idlelib/rpc.py", line 324, in putmessage
    s = pickle.dumps(message)
  File "/usr/local/Cellar/python/2.7.6/Frameworks/Python.framework/Versions/2.7/lib/python2.7/copy_reg.py", line 70, in _reduce_ex
    raise TypeError, "can't pickle %s objects" % base.__name__
TypeError: can't pickle _ElementUnicodeResult objects

我尝试检查标题

r.headers

退货

{'charset': 'utf-8',
 'x-powered-by': 'PHP/5.3.3',
 'transfer-encoding': 'chunked',
 'set-cookie': 'PHPSESSID=c6i7kph59nl9ocdlkckmjavas1; path=/, LOGIN_USER=deleted; expires=Tue, 15-Oct-2013 15:12:08 GMT; path=/',
 'expires': 'Thu, 19 Nov 1981 08:52:00 GMT',
 'server': 'Apache/2.2.15 (CentOS)',
 'connection': 'close',
 'pragma': 'no-cache',
 'cache-control': 'no-store, no-cache, must-revalidate, post-check=0, pre-check=0',
 'date': 'Wed, 15 Oct 2014 15:12:09 GMT',
 'content-type': 'text/html; charset=UTF-8'}

我的目标是能够通过xpath这样搜索树：

quantity = tree.xpath('/html/body/form[1]/table[3]/tbody[1]/tr/td[2]/table/tbody/tr/td[1]/table/tbody/tr/td/table[1]/tbody/tr[1]/td[2]/strong')

您能帮我确定我要去哪里了吗？

解决方法:

您应该能够将_ElementUnicodeResult对象转换为常规的可腌制unicode字符串.

使用Python 2时,只需使用unicode()将其包装起来,例如打印unicode(tree.text_content())

对于Python 3,只需将其包装在str()中,例如str(tree.text_content())

标签：python-requests,xpath,lxml,python
来源： https://codeday.me/bug/20191121/2049620.html