XSLT 1.0 escaping double quotes and backslash in a string

Question

I have a string like below and trying to convert into json format:

Test "out" and \new

Expected output is Test \"out\" and \new

I tried by calling templates for escapequote - working fine for escape quotes:

<xsl:template name="escapeQuote">
    <xsl:param name="pText" select="concat(normalize-space(.), '')" />
    <xsl:if test="string-length($pText) >0">
        <xsl:value-of select="substring-before(concat($pText, '&quot;'), '&quot;')" />

        <xsl:if test="contains($pText, '&quot;')">
            <xsl:text>\"</xsl:text>    
            <xsl:call-template name="escapeQuote">
                <xsl:with-param name="pText" select="substring-after($pText, '&quot;')" />
            </xsl:call-template>
        </xsl:if>
    </xsl:if>
</xsl:template>

Template for escape backslash - working for only backslash:

<xsl:template name="jsonescape">
 <xsl:param name="str" select="."/>
  <xsl:choose>
    <xsl:when test="contains($str, '\')">
      <xsl:value-of select="concat(substring-before($str, '\'), '\\' )"/>
      <xsl:call-template name="jsonescape">
        <xsl:with-param name="str" select="substring-after($str, '\')"/>
      </xsl:call-template>
    </xsl:when>
    <xsl:otherwise>
        <xsl:value-of select="$str"/>
    </xsl:otherwise>
  </xsl:choose>
</xsl:template>

My question how to call both templates or merge, please help me

Answer 1

Here is an example of how you can combine the two template calls, so that the output from jsonescape is used as an input parameter to escapequote

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
  <xsl:output method="text" />

  <xsl:template match="input">
    <xsl:call-template name="escapeQuote">
      <xsl:with-param name="pText">
        <xsl:call-template name="jsonescape">
          <xsl:with-param name="str" select="." />
        </xsl:call-template>          
      </xsl:with-param>
    </xsl:call-template>
  </xsl:template>

  <xsl:template name="escapeQuote">
      <xsl:param name="pText" select="concat(normalize-space(.), '')" />
      <xsl:if test="string-length($pText) >0">
          <xsl:value-of select="substring-before(concat($pText, '&quot;'), '&quot;')" />

          <xsl:if test="contains($pText, '&quot;')">
              <xsl:text>\"</xsl:text>    
              <xsl:call-template name="escapeQuote">
                  <xsl:with-param name="pText" select="substring-after($pText, '&quot;')" />
              </xsl:call-template>
          </xsl:if>
      </xsl:if>
  </xsl:template>

  <xsl:template name="jsonescape">
   <xsl:param name="str" select="."/>
    <xsl:choose>
      <xsl:when test="contains($str, '\')">
        <xsl:value-of select="concat(substring-before($str, '\'), '\\' )"/>
        <xsl:call-template name="jsonescape">
          <xsl:with-param name="str" select="substring-after($str, '\')"/>
        </xsl:call-template>
      </xsl:when>
      <xsl:otherwise>
          <xsl:value-of select="$str"/>
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>
</xsl:stylesheet>

So, given this an input:

<input>Test "out" and \new</input>

The following is output

Test \"out\" and \\new

Note that the order is important, because if you reversed the order of the template calls, the " would get converted to \" by the escapequote template, which would then get converted to \\" by the jsonescape template.

Alternatively, as both template do a similar thing, of putting a \ before specific characters, you could combine the two templates into one.

Try this XSLT too

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="2.0">
  <xsl:output method="text" />

  <xsl:template match="input">
    <xsl:call-template name="jsonescape">
      <xsl:with-param name="str" select="." />
    </xsl:call-template>          
  </xsl:template>

  <xsl:template name="jsonescape">
   <xsl:param name="str" select="."/>
   <xsl:param name="escapeChars" select="'\&quot;'" />
   <xsl:variable name="first" select="substring(translate($str, translate($str, $escapeChars, ''), ''), 1, 1)" />
   <xsl:choose>
      <xsl:when test="$first">
        <xsl:value-of select="concat(substring-before($str, $first), '\', $first)"/>
        <xsl:call-template name="jsonescape">
          <xsl:with-param name="str" select="substring-after($str, $first)"/>
        </xsl:call-template>
      </xsl:when>
      <xsl:otherwise>
          <xsl:value-of select="$str"/>
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>
</xsl:stylesheet>