How do I Emit Escaped XML representation of a Node in my XSLT's HTML Output
I'm transforming XML to an HTML document. In this document I want to embed XML markup for a node that was just transformed (the HTML document is a technical spec).
For example, if my XML was this:
<transform-me>
<node id="1">
<stuff type="floatsam">
<details>Various bits</details>
</stuff>
</node>
</transform-me>
I'd want my XSLT output to loo开发者_开发技巧k something like this:
<h1>Node 1</h1>
<h2>Stuff (floatsam)</h2>
Various bits
<h2>The XML</h2>
<stuff type="floatsam">
<details>Various bits</details>
</stuff>
I'm hoping there is an XSLT function that I can call in my <stuff> template to which I can pass the current node (.) and get back escaped XML markup for <stuff> and all its descendants. I have a feeling unparsed-text() might be the way to go but can't get it to work.
Very simple template
<xsl:template match="node()" mode="print">
<xsl:choose>
<!-- is it element? -->
<xsl:when test="name()">
<!-- start tag -->
<xsl:text><</xsl:text>
<xsl:value-of select="name()" />
<!-- attributes -->
<xsl:apply-templates select="@*" mode="print" />
<xsl:choose>
<!-- has children -->
<xsl:when test="node()">
<!-- closing bracket -->
<xsl:text>></xsl:text>
<!-- children -->
<xsl:apply-templates mode="print" />
<!-- end tag -->
<xsl:text></</xsl:text>
<xsl:value-of select="name()" />
<xsl:text>></xsl:text>
</xsl:when>
<!-- is empty -->
<xsl:otherwise>
<!-- closing bracket -->
<xsl:text>/></xsl:text>
</xsl:otherwise>
</xsl:choose>
</xsl:when>
<!-- text -->
<xsl:otherwise>
<xsl:copy />
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<xsl:template match="@*" mode="print">
<xsl:text> </xsl:text>
<xsl:value-of select="name()" />
<xsl:text>="</xsl:text>
<xsl:value-of select="." />
<xsl:text>"</xsl:text>
</xsl:template>
Used
<xsl:apply-templates mode="print" />
You can even add pretty printing if you want.
The answer to this is more complex that you would at first think. Proper "double-escaping" of attribute values and text nodes must occur.
This XSLT 1.0 template does a correct (though not complete) printing of an XML node, including (an attempt to do) proper pretty-printing with configurable indentation:
<xsl:stylesheet
version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
>
<xsl:output method="html" encoding="utf-8" />
<!-- defaults and configurable parameters -->
<xsl:param name="NL" select="'
'" /><!-- newline sequence -->
<xsl:param name="INDENTSEQ" select="'	'" /><!-- indent sequence -->
<xsl:variable name="LT" select="'<'" />
<xsl:variable name="GT" select="'>'" />
<xsl:template match="transform-me">
<html>
<body>
<!-- this XML-escapes an entire sub-structure -->
<pre><xsl:apply-templates select="*" mode="XmlEscape" /></pre>
</body>
</html>
</xsl:template>
<!-- element nodes will be handled here, incl. proper indenting -->
<xsl:template match="*" mode="XmlEscape">
<xsl:param name="indent" select="''" />
<xsl:value-of select="concat($indent, $LT, name())" />
<xsl:apply-templates select="@*" mode="XmlEscape" />
<xsl:variable name="HasChildNode" select="node()[not(self::text())]" />
<xsl:variable name="HasChildText" select="text()[normalize-space()]" />
<xsl:choose>
<xsl:when test="$HasChildNode or $HasChildText">
<xsl:value-of select="$GT" />
<xsl:if test="not($HasChildText)">
<xsl:value-of select="$NL" />
</xsl:if>
<!-- render child nodes -->
<xsl:apply-templates mode="XmlEscape" select="node()">
<xsl:with-param name="indent" select="concat($INDENTSEQ, $indent)" />
</xsl:apply-templates>
<xsl:if test="not($HasChildText)">
<xsl:value-of select="$indent" />
</xsl:if>
<xsl:value-of select="concat($LT, '/', name(), $GT, $NL)" />
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="concat(' /', $GT, $NL)" />
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<!-- comments will be handled here -->
<xsl:template match="comment()" mode="XmlEscape">
<xsl:param name="indent" select="''" />
<xsl:value-of select="concat($indent, $LT, '!--', ., '--', $GT, $NL)" />
</xsl:template>
<!-- text nodes will be printed XML-escaped -->
<xsl:template match="text()" mode="XmlEscape">
<xsl:if test="not(normalize-space() = '')">
<xsl:call-template name="XmlEscapeString">
<xsl:with-param name="s" select="." />
<xsl:with-param name="IsAttribute" select="false()" />
</xsl:call-template>
</xsl:if>
</xsl:template>
<!-- attributes become a string: '{name()}="{escaped-value()}"' -->
<xsl:template match="@*" mode="XmlEscape">
<xsl:value-of select="concat(' ', name(), '="')" />
<xsl:call-template name="XmlEscapeString">
<xsl:with-param name="s" select="." />
<xsl:with-param name="IsAttribute" select="true()" />
</xsl:call-template>
<xsl:value-of select="'"'" />
</xsl:template>
<!-- template to XML-escape a string -->
<xsl:template name="XmlEscapeString">
<xsl:param name="s" select="''" />
<xsl:param name="IsAttribute" select="false()" />
<!-- chars &, < and > are never allowed -->
<xsl:variable name="step1">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$s" />
<xsl:with-param name="search" select="'&'" />
<xsl:with-param name="replace" select="'&amp;'" />
</xsl:call-template>
</xsl:variable>
<xsl:variable name="step2">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$step1" />
<xsl:with-param name="search" select="'<'" />
<xsl:with-param name="replace" select="'&lt;'" />
</xsl:call-template>
</xsl:variable>
<xsl:variable name="step3">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$step2" />
<xsl:with-param name="search" select="'>'" />
<xsl:with-param name="replace" select="'&gt;'" />
</xsl:call-template>
</xsl:variable>
<!-- chars ", TAB, CR and LF are never allowed in attributes -->
<xsl:choose>
<xsl:when test="$IsAttribute">
<xsl:variable name="step4">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$step3" />
<xsl:with-param name="search" select="'"'" />
<xsl:with-param name="replace" select="'&quot;'" />
</xsl:call-template>
</xsl:variable>
<xsl:variable name="step5">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$step4" />
<xsl:with-param name="search" select="'	'" />
<xsl:with-param name="replace" select="'&#x9;'" />
</xsl:call-template>
</xsl:variable>
<xsl:variable name="step6">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$step5" />
<xsl:with-param name="search" select="'
'" />
<xsl:with-param name="replace" select="'&#xD;'" />
</xsl:call-template>
</xsl:variable>
<xsl:variable name="step7">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$step6" />
<xsl:with-param name="search" select="'
'" />
<xsl:with-param name="replace" select="'&#xD;'" />
</xsl:call-template>
</xsl:variable>
<xsl:value-of select="$step7" />
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="$step3" />
</xsl:otherwise>
</xsl:choose>
</xsl:template>
<!-- generic string replace template -->
<xsl:template name="StringReplace">
<xsl:param name="s" select="''" />
<xsl:param name="search" select="''" />
<xsl:param name="replace" select="''" />
<xsl:choose>
<xsl:when test="contains($s, $search)">
<xsl:value-of select="substring-before($s, $search)" />
<xsl:value-of select="$replace" />
<xsl:variable name="rest" select="substring-after($s, $search)" />
<xsl:if test="$rest">
<xsl:call-template name="StringReplace">
<xsl:with-param name="s" select="$rest" />
<xsl:with-param name="search" select="$search" />
<xsl:with-param name="replace" select="$replace" />
</xsl:call-template>
</xsl:if>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="$s" />
</xsl:otherwise>
</xsl:choose>
</xsl:template>
</xsl:stylesheet>
When applied to this test XML:
<transform-me>
<node id="1">
<!-- a comment -->
<stuff type="fl"' 	oatsam">
<details>Various bits & pieces</details>
<details>
</details>
<details attr="value">
<childnode>text and <escaped-text /></childnode>
</details>
</stuff>
</node>
</transform-me>
The following output is produced (source code):
<html>
<body>
<pre><node id="1">
<!-- a comment -->
<stuff type="fl&quot;'&#xD;&#x9;oatsam">
<details>Various bits &amp; pieces</details>
<details />
<details attr="value">
<childnode>text and &lt;escaped-text /&lt;</childnode>
</details>
</stuff>
</node>
</pre>
</body>
</html>
and when viewed in the browser you see:
<node id="1">
<!-- a comment -->
<stuff type="fl"'
	oatsam">
<details>Various bits & pieces</details>
<details />
<details attr="value">
<childnode>text and <escaped-text /<</childnode>
</details>
</stuff>
</node>
Note that by "not complete" I mean that things like namespaces and processing instructions for example are currently unhandled. But its easy to make a template for them.
加载中,请稍侯......
精彩评论