问题描述
我需要用段落包装所有纯文本块,但可能有一个嵌套的段落应该被跳过。我将如何解决这个问题?
我很难理解如何在跳过现有段落的同时将一些纯文本包装成一个段落。
给定的 XML:
<section xmlns="http://www.w3.org/1999/xhtml">
<div>
test test
<p>test</p>
<ins>INS</ins>
text
</div>
</section>
预期结果:
<section xmlns="http://www.w3.org/1999/xhtml">
<div>
<p>test test</p>
<p>test</p>
<p>
<ins>INS</ins>
text
</p>
</div>
</section>
解决方法
这里是一种使用简单的递归算法通过 p 个节点有效划分 div 内容的方法
declare default element namespace "http://www.w3.org/1999/xhtml";
declare function local:collect($sequence as node()*) as node()* {
(: index of last p in this candidate subsequence :)
let $nextP := max((0,(for $i in (1 to count($sequence))
where $sequence[$i][self::p]
return $i)))
return
(: if sequence is empty then return empty sequence :)
if(count($sequence) = 0) then ()
(: if no p in this candidate subsequence,then wrap it in a p :)
else if($nextP = 0) then <p>{$sequence}</p>
(: otherwise evaluate subsequence before the last p,the p,and the subsequence after the last p
:)
else (
local:collect(subsequence($sequence,1,$nextP - 1)),$sequence[$nextP],local:collect(subsequence($sequence,$nextP + 1))
)
};
let $input :=
<section>
<div>
test test
<p>test</p>
<ins>INS</ins>
text
</div>
</section>
return
<section>
{
for $div in $input/div
return <div>{local:collect($div/(*|text()))}</div>
}
</section>
产生以下结果:
<section xmlns="http://www.w3.org/1999/xhtml">
<div>
<p>
test test
</p>
<p>test</p>
<p><ins>INS</ins>
text
</p>
</div>
</section>
您的预期结果与文本节点中的前导/尾随空格不一致。目前尚不清楚您是否真的希望获得针对某些文本而不是其他文本规范化空格的确切结果。可能不会。
要规范化所有文本节点中的空白,请替换:
<p>{$sequence}</p>
与:
<p>{for $x in $sequence return if($x[self::text()]) then normalize-space($x) else ($x)}</p>
产生:
<section xmlns="http://www.w3.org/1999/xhtml">
<div>
<p>test test</p>
<p>test</p>
<p><ins>INS</ins>text</p>
</div>
</section>
这里的算法在没有 p 或多个 p 时有效,但我没有测试每个场景。
在 XQuery 3 中,这可以通过滚动窗口来简化,例如:
(: Return true if the passed nodes exist and both p or neither are p.
:)
declare function local:same($compare1 as node()?,$compare2 as node()?) as xs:boolean {
if(not($compare1) or not($compare2)) then false()
else if(($compare1[self::p] and $compare2[self::p])
or (not($compare1[self::p]) and not($compare2[self::p])))
then true()
else false()
};
let $input :=
<section>
<div>
test test
<p>test</p>
<ins>INS</ins>
text
</div>
</section>
return
<section>
{
for $div in $input/div
return
<div>
{
for tumbling window $partition in $div/(*|text())
start $s previous $s-prev when not(local:same($s,$s-prev))
end $e next $e-next when not(local:same($e,$e-next))
return
if($partition[1][self::p])
then $partition
else <p>{$partition}</p>
}
</div>
}
</section>
与规范化空间类似,替换:
<p>{$partition}</p>
类似的东西
<p>{for $x in $partition return if($x[self::text()]) then normalize-space($x) else ($x)}</p>