html - 如何使用 XSLT 将 HTML 百分比编码转换为 Unicode？

Question

网上有大量关于此的条目和答案，但它们都与我需要的方向相反。从我的 iTunes XML 中，我有数千个百分比编码的条目，使用多种语言，我试图使用 XSLT 样式表将它们转换为 Unicode 文本。除了追踪每个字符并进行替换之外，我是否缺少任何功能或过程？这是我正在使用的一些例子的小样本，第一行是 XML 字符串值，下一行是我试图生成并输出到文本文件的基本文本。

<string>/iTunes/iTunes%20Music/Droit%20devant/L'odysse%CC%81e.mp3</string>

/iTunes/iTunes Music/Droit devant/L'odyssée.mp3

<string>A%CC%80%20la%20Pe%CC%82che</string>

À la Pêche

<string>%D0%97%D0%B0%D0%BF%D0%BE%D0%BC%D0%B8%D0%BD%D0%B0%D0%B8%CC%86</string>

Запоминай

<string>%CE%9A%CE%BF%CC%81%CF%84%CF%83%CC%8C%CE%B1%CF%81%CE%B9</string>

κότσ̌αρι

由于过度突出的 hacek/caron，最后一个对于某些人可能无法正确显示。

提前感谢您的任何建议或线索

Answer 1

纯 XSLT 2.0 解决方案可以使用 string-to-codepoints()和 codepoints-to-string()职能。 utf-8解码有点乱，可以搞定。

此 XSLT 2.0 样式表...

<xsl:stylesheet version="2.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"
  xmlns:so="http://stackoverflow.com/questions/13768754"
  exclude-result-prefixes="xsl xs so">
<xsl:output encoding="UTF-8" omit-xml-declaration="yes" indent="yes" />
<xsl:strip-space elements="*"/>

<xsl:variable name="cp-base" select="string-to-codepoints('0A')" as="xs:integer+" />

<xsl:template match="@*|node()">
  <xsl:copy>
    <xsl:apply-templates select="@*|node()" />
  </xsl:copy>
</xsl:template>

<xsl:function name="so:utf8decode" as="xs:integer*">
  <xsl:param name="bytes" as="xs:integer*" />
  <xsl:choose>
    <xsl:when test="empty($bytes)" />
    <xsl:when test="$bytes[1] eq 0"><!-- The null character is not valid for XML. -->
      <xsl:sequence select="so:utf8decode( remove( $bytes, 1))" />
    </xsl:when>
    <xsl:when test="$bytes[1] le 127">
      <xsl:sequence select="$bytes[1], so:utf8decode( remove( $bytes, 1))" />
    </xsl:when>
    <xsl:when test="$bytes[1] lt 224">
      <xsl:sequence select="
      ((($bytes[1] - 192) * 64) +
        ($bytes[2] - 128)        ),
        so:utf8decode( remove( remove( $bytes, 1), 1))" />
    </xsl:when>
    <xsl:when test="$bytes[1] lt 240">
      <xsl:sequence select="
      ((($bytes[1] - 224) * 4096) +
       (($bytes[2] - 128) *   64) +
        ($bytes[3] - 128)          ),
        so:utf8decode( remove( remove( remove( $bytes, 1), 1), 1))" />
    </xsl:when>
    <xsl:when test="$bytes[1] lt 248">
      <xsl:sequence select="
      ((($bytes[1] - 240) * 262144) +
       (($bytes[2] - 128) *   4096) +
       (($bytes[3] - 128) *     64) +
        ($bytes[4] - 128)            ),
        so:utf8decode( $bytes[position() gt 4])" />
    </xsl:when>
    <xsl:otherwise>
      <!-- Code-point valid for XML. -->
      <xsl:sequence select="so:utf8decode( remove( $bytes, 1))" />
    </xsl:otherwise>
  </xsl:choose>
</xsl:function>

<xsl:template match="string/text()">
  <xsl:analyze-string select="." regex="(%[0-9A-F]{{2}})+" flags="i">
    <xsl:matching-substring>
      <xsl:variable name="utf8-bytes" as="xs:integer+">
        <xsl:analyze-string select="." regex="%([0-9A-F]{{2}})" flags="i">
          <xsl:matching-substring>
          <xsl:variable name="nibble-pair" select="
            for $nibble-char in string-to-codepoints( upper-case(regex-group(1))) return
              if ($nibble-char ge $cp-base[2]) then
                  $nibble-char - $cp-base[2] + 10
                else
                  $nibble-char - $cp-base[1]" as="xs:integer+" />
            <xsl:sequence select="$nibble-pair[1] * 16 + $nibble-pair[2]" />                
          </xsl:matching-substring>
        </xsl:analyze-string>
      </xsl:variable>
      <xsl:value-of select="codepoints-to-string( so:utf8decode( $utf8-bytes))" />
    </xsl:matching-substring>
    <xsl:non-matching-substring>
      <xsl:value-of select="." />
    </xsl:non-matching-substring>
    <xsl:fallback>
      <!-- For XSLT 1.0 operating in forward compatibility mode,
           just echo -->
      <xsl:value-of select="." />
    </xsl:fallback>
  </xsl:analyze-string>
</xsl:template>

</xsl:stylesheet>

...应用于此输入...

<doc>
    <string>/iTunes/iTunes%20Music/Droit%20devant/L'odysse%CC%81e.mp3</string>
    <string>A%Cc%80%20la%20Pe%CC%82che</string>
    <string>%D0%97%D0%B0%D0%BF%D0%BE%D0%BC%D0%B8%D0%BD%D0%B0%D0%B8%CC%86</string>
    <string>%CE%9A%CE%BF%CC%81%CF%84%CF%83%CC%8C%CE%B1%CF%81%CE%B9</string>
</doc>

..产量..

<doc>
   <string>/iTunes/iTunes Music/Droit devant/L'odyssée.mp3</string>
   <string>À la Pêche</string>
   <string>Запоминай</string>
   <string>Κότσ̌αρι</string>
</doc>