Xpath

Question

<html>
    <table border="1">
        <tbody>
            <tr>
                <td>
                    <table border="1">
                        <tbody>
                            <tr>
                                <th>aaa</th>
                                <th>bbb</th>
                                <th>ccc</th>
                                <th>ddd</th>
                                <th>eee</th>
                                <th>fff</th>
                            </tr>
                            <tr>
                                <td>111</td>
                                <td>222</td>
                                <td>333</td>
                                <td>444</td>
                                <td>555</td>
                                <td>666</td>
                            </tr>
                        </tbody>
                    </table>
                </td>
            </tr>
        </tbody>
    </table>
</html>

如何使用 xpath select 特定的相关表亲数据，所需的输出将是：

<th>aaa</th>
<th>ccc</th>
<th>fff</th>
<td>111</td>
<td>333</th>
<td>666</td>

xpath 最重要的方面是我希望能够包含或排除某些 <th> 标签及其相应的 <td> 标签

所以根据目前为止我最接近的答案是：

//th[not(contains(text(), "ddd"))] | //tr[2]/td[not(position()=4)]

有什么方法可以不显式使用 position()=4 而是引用相应的 th 标签

Answer 1

我不确定这是最好的解决方案，但您可以试试

//th[not(.="bbb") and not(.="ddd") and not(.="eee")] | //tr[2]/td[not(position()=index-of(//th, "bbb")) and not(position()=index-of(//th, "ddd")) and not(position()=index-of(//th, "eee"))]

或更短的版本

//th[not(.=("bbb", "ddd", "eee"))]| //tr[2]/td[not(position()=(index-of(//th, "bbb"), index-of(//th, "ddd"),index-of(//th, "eee")))]

that returns

<th>aaa</th>
<th>ccc</th>
<th>fff</th>
<td>111</td>
<td>333</td>
<td>666</td>

您可以避免使用复杂的 XPath 表达式来获得所需的输出。尝试使用 Python + Selenium 功能：

# Get list of th elements
th_elements = driver.find_elements_by_xpath('//th')
# Get list of td elements
td_elements = driver.find_elements_by_xpath('//tr[2]/td')
# Get indexes of required th elements - [0, 2, 5]
ok_index = [th_elements.index(i) for i in th_elements if i.text not in ('bbb', 'ddd', 'eee')]
for i in ok_index:
    print(th_elements[i].text)
for i in ok_index:
    print(td_elements[i].text)

输出为

'aaa'
'ccc'
'fff'
'111'
'333'
'666'

如果您需要XPath 1.0解决方案：

//th[not(.=("bbb", "ddd", "eee"))]| //tr[2]/td[not(position()=(count(//th[.="bbb"]/preceding-sibling::th)+1, count(//th[.="ddd"]/preceding-sibling::th)+1, count(//th[.="eee"]/preceding-sibling::th)+1))]

Answer 2

使用 XPath 3.0，您可以将其结构化为

let $th := //table/tbody/tr[1]/th, 
$filteredTh := $th[not(. = ("bbb", "ddd", "eee"))], 
$pos := $filteredTh!index-of($th, .)
return ($filteredTh, //table/tbody/tr[position() gt 1]/td[position() = $pos])

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