XSLT - Remove currency formatting and check if number, otherwise pass as string

Question

I need to remove currency formatting from a string, but my problem is that the field sometimes contains currency and sometimes it is a string of text. So it could be:

$20
123,000.00
$123,000.00
Hello World!

Answer 1

As a single XPATH test if the string could be evaluated as a number and return boolean:

number(translate(.,translate(.,'0123456789.',''),''))

You could put it into a template like this to return either a parsed number or nothing:

<xsl:template name="getNumber">
    <xsl:param name="stringVal" />
     <!--remove all characters other than number and period, use the result in the outer replace to yield only numbers and period -->
    <xsl:variable name="numVal" select="translate(.,translate(.,'0123456789.',''),'')" />
    <xsl:choose>
        <!--If what is left evaluates as a number, then it's a number! -->
        <xsl:when test="number($numVal)">
            <xsl:value-of select="$numVal"/>
        </xsl:when>
        <xsl:otherwise>
            <!--Do nothing-->
        </xsl:otherwise>
    </xsl:choose>
</xsl:template>

Call the template like this:

    <xsl:call-template name="getNumber">
        <xsl:with-param name="stringVal" select="." />
    </xsl:call-template>