Defining and using variables in XSL

Question

I have an xsl file with variables and parameters. Parameters are defined in another xml file:

<fo:block><xsl:value-of select="root/period"/></fo:block>

and the parameter has the value:

<root>
  <period>1-5</period>
</root>

Now, sometimes I want to display the block, containing the period, sometimes I don't. How can I achieve this? Here is how I tried:

<xsl:variable name="cond" select="root/cond"/>
<xsl:if test="$cond='1'">
  <fo:block><xsl:value-of select="root/period"/></fo:block>
</xsl:if>

parameters:

<root>
  <cond>1</cond>
  <period>1-5</period>
</root>

This does not work! I displayed the value of the variable using <xsl:copy-of select="$cond" /> and it's empty.

UPDATE:

I know now what the problem is:

xsl-fo:

<fo:flow flow-name="xsl-region-body">
  <fo:block>
    test
  </fo:block>
  <fo:block>
    <xsl:variable name="cond" select=root/cond/>
    <xsl:copy-of select="$cond" />
  </fo:block>
  <fo:block>
    <xsl:value-of select="root/period"/>
  </fo:block>
</fo:flow>

parameters:

<root>
  <cond>haha</cond>
  <period>01.01.2013 – 31.12.2013</period>
</root>

output:

test 01.01.2013 – 31.12.2013

So the question is really: how can I select a value from the xml parameters and assign the value to a xsl variable?

Answer 1

And here is the solution:

<xsl:variable name="firstLine">
  <xsl:value-of select="root/firstLine"/>
</xsl:variable>

That't how you get the value from the parameters (xml).

Answer 2

A couple of things.

First of all, the updated XSL-FO you showed is not well-formed:

<xsl:variable name="cond" select=root/cond/>

The select attribute value needs quotes around it:

<xsl:variable name="cond" select="root/cond" />

I assume this is not really the problem, because if it were, you'd be getting no output at all, just an error.

But I think your real problem is where you say

<xsl:copy-of select="$cond" />

Since you are using copy-of instead of value-of, this copies the nodes in the $cond variable to the output. So your output FO will include the element <cond>haha</cond>. I don't know what an FO processor is supposed to do with elements like this that are in no namespace. Apparently, outputting the text content is not what it does; it probably ignores them.

Try changing that copy-of to value-of:

<xsl:value-of select="$cond" />

This will put haha into the output, without the <cond> element around it. Try this, and if it doesn't do what you expect, tell us

1. what FO output you got (the output of the stylesheet before the FO processor runs)
2. and what final output you got (output of the FO processor)
3. and how these differ from what you expected.