Question

我有一个收集条目和压缩它们的功能，然后以epub的形式提供给用户。问题是我收集每一章作为<entry/>元素，这意味着没有根元素。我只有一个带有章节数组的变量。有什么方法可以解决这个问题吗？

例如：

let $chaps := (
    <entry>
        <html>
            <h1>abc</h1>
            <h2>xxx</h2>
            <h2>yyy</h2>
        </html>
    </entry>,
    <entry>
        <html>
            <h1>def</h1>
            <h2>xxx</h2>
            <h2>yyy</h2>
        </html>
    </entry>,
    <entry>
        <html>
            <h1>ghi</h1>
            <h2>xxx</h2>
            <h2>yyy</h2>
        </html>
    </entry>,
    <entry>
        <html>
            <h1>jkl</h1>
            <h2>xxx</h2>
            <h2>yyy</h2>
        </html>
    </entry>
)

我在尝试：

for $entry in $chaps
return 
    <headings>
        <a>{'Count h1 in preceding entries: ' || count($entry/preceding-sibling::entry//h1)}</a>
        <b>{'Count h2 in preceding entries: ' || count($entry/preceding-sibling::entry//h2)}</b>
    </headings>

结果：

<headings>
    <a>Count h1 in preceding entries: 0</a>
    <b>Count h2 in preceding entries: 0</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 0</a>
    <b>Count h2 in preceding entries: 0</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 0</a>
    <b>Count h2 in preceding entries: 0</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 0</a>
    <b>Count h2 in preceding entries: 0</b>
</headings>

预期：

<headings>
    <a>Count h1 in preceding entries: 0</a>
    <b>Count h2 in preceding entries: 0</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 1</a>
    <b>Count h2 in preceding entries: 2</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 2</a>
    <b>Count h2 in preceding entries: 4</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 3</a>
    <b>Count h2 in preceding entries: 6</b>
</headings>

Answer 1

如果我理解你的话：

count($entry//preceding::xhtml:h1)

没有产生您的预期结果，因为您想要计算h1之前显示的entry？

如果是这样，请不要使用//，因为这意味着自我或后代，相反，我认为您需要类似的内容：

$entry/preceding-sibling::entry//xhtml:h1

Answer 2

因为在变量内部确实存在一个数组，所以需要迭代数组，而不是单独使用变量。最后，这对我有用：

for $entry at $index in $chaps
return 
    <headings>
        <a>{'Count h1 in preceding entries: ' || count(
                for $i in 1 to $index
                return $entry//xhtml:h1
        )}</a>
        <b>{'Count h1 in preceding entries: ' || count(
                for $i in 1 to $index
                return $entry//xhtml:h2
        )}</b>
    </headings>

结果：

<headings>
    <a>Count h1 in preceding entries: 1</a>
    <b>Count h1 in preceding entries: 2</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 2</a>
    <b>Count h1 in preceding entries: 4</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 3</a>
    <b>Count h1 in preceding entries: 6</b>
</headings>
<headings>
    <a>Count h1 in preceding entries: 4</a>
    <b>Count h1 in preceding entries: 8</b>
</headings>

Answer 3

Simpler implementation possible using the position() function. I think this is what you were aiming at originally:

for $a at $pos in $chaps
return 
<headings>
        <a>{'Count h1 in preceding entries: ' || count($chaps[position() < $pos]//h1)}</a>
        <b>{'Count h2 in preceding entries: ' || count($chaps[position() < $pos]//h2)}</b>
    </headings>

计算节点数组中的元素

3 个答案: