Question

使用这个python代码，我可以获得整个html源代码

import mechanize
import lxml.html
import StringIO

br = mechanize.Browser()
br.set_handle_robots(False)
br.addheaders = [("User-agent","Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.2.13) Gecko/20101206 Ubuntu/10.10 (maverick) Firefox/3.6.13")]
sign_in = br.open("http://target.co.uk")
#the login url
br.select_form(nr = 0) 
#accessing form by their index.
#Since we have only one form in this example, nr =0.
br.select_form(nr=0)
#Alternatively you may use this instead of the above line 
#if your form has name attribute available.
br["username"] = "myusername"
#the key "username" is the variable that takes the username/email value
br["password"] = "myp4sw0rd"
#the key "password" is the variable that takes the password value
logged_in = br.submit()   
#submitting the login credentials
logincheck = logged_in.read()
#reading the page body that is redirected after successful login
if "logout" in logincheck:
    print "Login success, you just logged in."
else:
    print "Login failed"
#printing the body of the redirected url after login
coding1_content = br.open("https://www.target.co.uk/levels/coding/1").read() 
#accessing other url(s) after login is done this way


tree = lxml.html.parse(io.StringIO(coding1_content)

for ta in tree.findall("//textarea"):
    if not ta.get("name"):
        print(ta.text)

if "textarea" in coding1_content:
    print "Textarea found."
else:
    print "Textarea not found."

但我需要的是获取第一个textarea标签的内容，其中没有名称，我的html源代码如下

........
........
<textarea>this, is, what, i, want</textarea>
<textarea name="answer">i don't need it</textarea>
........
........

任何帮助将不胜感激

Answer 1

根据lxml文档，您可以通过访问forms属性来访问html对象的表单：

form_page = fromstring('''some html code with a <form>''')
form = form_page.forms[0] # to get the first form
form.fields # these are the fields

在此处查看更多内容：http://lxml.de/lxmlhtml.html - ＆gt;表格

Answer 2

如果HTML是

<html>
  <body>
    <form>
      <textarea>this, is, what, i, want</textarea>
      <textarea name="answer">i don't need it</textarea>
    </form>
  </body>
</html>

您可以获得textarea这样的内容：

import io
import lxml.html

html = "..."
tree = lxml.html.parse(io.StringIO(html)
for ta in tree.findall("//textarea"):
    if not ta.get("name"):
        print(ta.text)

输出：

this, is, what, i, want

Answer 3

让所有<textarea>没有HTML属性name的另一种可能方法，即使用xpath()方法：

.....
for t in tree.xpath(".//textarea[not(@name)]"):
    print t.text

虽然findall()仅支持XPath语言的子集，但xpath()具有完整的XPath 1.0支持。例如，正如此特定情况所示，xpath()支持not()而findall()则不支持。{/ p>

如何使用lxml python获取textarea值

3 个答案: