lxml.html parsing with XPath and variables
html, lxml, parsing, python, web-scraping
Solution
Your first example woks, but probably not how you think it shoud:
test=html.xpath("//ul[@class='toc']/li[@class='level2']/div[@class='li']/a/text()='One'")
What this returns is a boolean, which will be true if the condition `...='One'` is true for any of the nodes in the result set at the left side of the xpath expression. And that's why you get the error in your second example: `True[0]` is not valid.
You probalby want all nodes matching the expession, having `'One'` as text. The corresponding expression would be:
test=html.xpath("//ul[@class='toc']/li[@class='level2']/div[@class='li']/a[text()='One']")
This returns a nodeset as result, or if you just need the url as a string:
test=html.xpath("//ul[@class='toc']/li[@class='level2']/div[@class='li']/a[text()='One']/@href")
# returns: ['#link1']
Problem
I have this HTML snippet ``` <div id="dw__toc"> <h3 class="toggle">Table of Contents</h3> <div> <ul class="toc"> <li class="level1"><div class="li"><a href="#section">#</a></div> <ul class="toc"> <li class="level2"><div class="li"><a href="#link1">One</a></div></li> <li class="level2"><div class="li"><a href="#link2">Two</a></div></li> <li class="level2"><div class="li"><a href="#link3">Three</a></div></li> ``` Now I want to parse it with lxml.html. In the end I want a function where I can provide a searchterm (i.e. "one") and the function should return ``` One #link1 ``` For now I'm trying to get a variable in the XPath. Works: ``` import lxml.html html = lxml.html.parse("www.myurl.com/slash/something") test=html.xpath("//ul[@class='toc']/li[@class='level2']/div[@class='li']/a/text()='One'") print test ``` Trying with variable. I want to replace the hardcoded `'One'` with a variable which I can return to the function later. Doesn't work: ``` import lxml.html html = lxml.html.parse("www.myurl.com/slash/something") desiredvars = ['One'] myresultset=((var, html.xpath("//ul[@class='toc']/li[@class='level2']/div[@class='li']/a[text()='%s']"%(var))[0]) for var in desiredvars) for each in myresultset: print each Traceback (most recent call last): File "<stdin>", line 1, in <module> File "<stdin>", line 1, in <genexpr> IndexError: list index out of range ``` This is based on this answer: https://stackoverflow.com/a/10688235/2320453 Any idea why it doesn't work? Is this the "right way" to do something like this? EDIT: To sum things up: I want to search within the a-Tags and get the text from this Attributes, but I don't want a complete list instead I want to be able to search with a variable. Pseudo-code: ``` import lxml.html html = lxml.html.parse("www.myurl.com/slash/something") searchterm = 'one' test=html.xpath("...a/text()=searchterm") print test ``` Expected result ``` One #link1 ```