I have xpath
page.search("//table[#class='campaign']//table")
which returns two tables.
I need to choose only first table. This line doesn't work:
page.search("//table[#class='campaign']//table[1]")
How to choose only first table?
This bugged me, too. I still don't exactly know why your solution does not work. However, this should:
page.search("//table[#class='campaign']/descendant::table[1]")
EDIT: As the docs say,
"The location path //para[1] does not mean the same as the location
path /descendant::para[1]. The latter selects the first descendant
para element; the former selects all descendant para elements that are
the first para children of their parents."
Thanks to your question, I finally understood why this works this way :). So, depending on your structure and needs, this should work.
Instead of using an XPath expression to select the first matching element, you can either find all of them and then pare it down:
first_table = page.search("//table[#class='campaign']//table").first
...or better yet, select only the first by using at:
first_table = page.at("//table[#class='campaign']//table")
Note also that your expression can be found more simply by using the CSS selector syntax:
first_table = page.at("table.campaign table")
Related
I am trying to write an XPath expression which can return the URL associated with the next page of a search.
The URL which leads to the next page of the search is always the href in the a tag following the tag span class="navCurrentPage" I have been trying to use a following-sibling term to pull the next URL. My search in the Chrome console is:
$x('//span[#class="navCurrentPage"][1]/following-sibling::a/#href[1]')
I thought by specifying #href[1] I would only get back one URL (thinking the [1] chooses the first element in list), but instead Chrome (and Scrapy) are returning four URLs. I don't understand why. Please help me to understand how to select the one URL that I am looking for.
Here is the URL where you can find the HTML giving me trouble:
https://www.yachtworld.com/core/listing/cache/searchResults.jsp?cit=true&slim=quick&ybw=&sm=3&searchtype=advancedsearch&Ntk=boatsEN&Ntt=&is=false&man=&hmid=102&ftid=101&enid=0&type=%28Sail%29&fromLength=35&toLength=50&fromYear=1985&toYear=2010&fromPrice=&toPrice=&luom=126¤cyid=100&city=&rid=100&rid=101&rid=104&rid=105&rid=107&rid=108&rid=112&rid=114&rid=115&rid=116&rid=128&rid=130&rid=153&pbsint=&boatsAddedSelected=-1
Thank you for the help.
Operator precedence: //x[1] means /descendant-or-self::node()/child::x[1] which finds every descendant x that is the first child of its parent. You want (//x)[1] which finds the first node among all the descendants named x.
xpath index will apply on all matching records, if you want to get only the first item, get the first instance.
$x('//span[#class="navCurrentPage"][1]/following-sibling::a/#href[1]').extract_first()
just add, .extract_first() or .get() to fetch the first item.
see the scrapy documentation here.
I've found this very helpful to make sure you have the bracket in the right place.
What is the XPath expression to find only the first occurrence?
also, the first occurrence may be [0] not [1]
On this page
https://en.wikipedia.org/wiki/Trinity_Seven#Episode_list
I have:
//*[text()='Reception']//preceding::th[contains(#id, 'ep')]//following::I
But it only registers following.
The default firepath selector is: .//*[#id='mw-content-text']/div/table[5]/tbody/tr/td[1]/I but this kind of selector is known to break quite frequently. Just wondering if there is a better way of doing this and I thought this might be a way.
Thanks!
:)
- You can see that it's getting stuff under the table which is not what I want :S
Try to use below XPath to match required elements:
//th[contains(#id, 'ep')]/following::I[./following::*[text()='Reception']]
This looks more simple
//tr[contains(#class, 'vevent')]//i
Don't overcomplicate things. You need I tag inside each row. So just find row locator tr[contains(#class, 'vevent')] and get it's I
Another good approach in case you want to check that inside of parent element is located some special element, but you want to find some 3rd element is to use such style: //element[./specific]//child , so in your case:
//tr[contains(#class, 'vevent')][./th[contains(#id,'ep')]]//i
so it's I tag inside row that contains #id,'ep' in header
I am trying to quickly find a specific node using XPath but it seems my multiple predicates are not working. The div I need has a specific class, but there are 3 others that have it. I want to select the fourth one so I did the following:
//div[#class='myCLass' and 4]
However the "4" is being ignored. Any help? I am new to XPath.
Thanks.
If a xpath query returns a node set you can always use the [OFFSET] operator to access a certain element of it.
Use the following query to access the fourth element that matches the #class='myClass' predicate:
//div[#class='myCLass'][4]
#WilliamNarmontas answer might be an alternative to the syntax showed above.
Alternatively,
//div[#class='myCLass' and position()=4]
The accepted answer works correctly only if all of the div elements have the same parent. Otherwise use:
(//div[#class='myCLass'])[4]
I am trying to back to to previous td but to no avail, can you help
//*[#class='ein' and contains(.,'aaaa')] gets me to td but need to select the previous td-tried below but did not work
//*[#class='ein' and contains(.,'aaaa')][preceding-sibling::td]
Remember /X means "select X", while [X] means "where X". If you want to select preceding siblings, rather than testing whether they exist, use /.
It's impossible to say for certain without seeing the input HTML but I suspect that instead of
//*[#class='ein' and contains(.,'aaaa')][preceding-sibling::td]
you need something like
//*[#class='ein' and contains(.,'aaaa')]/preceding-sibling::td[1]
to navigate from each node selected by the initial expression to its nearest preceding td. Your first attempt will select exactly the same nodes as
//*[#class='ein' and contains(.,'aaaa')]
but only if they have at least one preceding-sibling element named td.
Use // after the element you found
Instead of preceding-sibling, just use preceding
//*[#class='ein' and contains(.,'aaaa')]//preceding::td[1]
I try to write xpath expressions so that my tests won't be broken by small design changes. So instead of the expressions that Selenium IDE generates, I write my own.
Here's an issue:
//input[#name='question'][7]
This expression doesn't work at all. Input nodes named 'question' are spread across the page. They're not siblings.
I've tried using intermediate expression, but it also fails.
(//input[#name='question'])[2]
error = Error: Element (//input[#name='question'])[2] not found
That's why I suppose Seleniun has a wrong implementation of XPath.
According to XPath docs, the position predicate must filter by the position in the nodeset, so it must find the seventh input with the name 'question'. In Selenium this doesn't work. CSS selectors (:nth-of-kind) neither.
I had to write an expression that filters their common parents:
//*[contains(#class, 'question_section')][7]//input[#name='question']
Is this a Selenium specific issue, or I'm reading the specs wrong way? What can I do to make a shorter expression?
Here's an issue:
//input[#name='question'][7]
This expression doesn't work at all.
This is a FAQ.
[] has a higher priority than //.
The above expression selects every input element with #name = 'question', which is the 7th child of its parent -- and aparently the parents of input elements in the document that is not shown don't have so many input children.
Use (note the brackets):
(//input[#name='question'])[7]
This selects the 7th element input in the document that satisfies the conditions in the predicate.
Edit:
People, who know Selenium (Dave Hunt) suggest that the above expression is written in Selenium as:
xpath=(//input[#name='question'])[7]
If you want the 7th input with name attribute with a value of question in the source then try the following:
/descendant::input[#name='question'][7]