Re: [xsl] Only output element when parameter value is not equal to blank (or null)

[Abel Braaksma <abel.online@xxxxxxxxx>]

Chris Coyle wrote:
> I tried:
>                                               <xsl:if
> test="exists($productid)">
> 					   <Attribute name="PRODUCTID"
> type="string"><xsl:value-of
> select="$productid"/></Attribute>
> 					</xsl:if>
>
> but got the following error:
> 06:47:27.062 global (ERROR) - Uncaught Exception:
> 'exists' is not a valid XSLT or XPath function.

exists() is an XPath 2 function, you use an XPath/XSLT 1 parser. But 
even if you weren't, it is not the right thing to do, exists($param) 
will always return true(), with one exception, when the variable returns 
an empty sequence:

<xsl:param name="myparam" select="()" />
or <xsl:param name="myparam" select="/.." />

then this yields false:
<xsl:if test="exists($myparam)" >....

However, with:

<xsl:param name="myparam" select=" '' " />
or <xsl:param name="myparam" select="0" />
or <xsl:param name="myparam"  />

then this yields true:
<xsl:if test="exists($myparam)" >....


Cheers!
-- Abel Braaksma