Hallo All,

I have an XML file with various hierarchy levels that I would like to get the user to navigate. I am using a key technique to group the data and it works fine ...

The user can select a PLANT and can view a consolidation of data for the teams that belong to the plant. That's great.

Now I would like to parameterize the whole thing so that, instead of selecting a PLANT the user can select a BUSINESS UNIT and can then see data for all the PLANTs in that BU. That's no problem if it's hard-coded but ...

When I try to plop in parameters the whole thing stops working. For example:

<xsl:apply-templates select="xmlout[(PERIOD=$pper and PLANT_CODE=$pplnt)]" mode="body">

... works fine ($pper supplies the PERIOD filter and $pplnt the PLANT). However, if I try to parameterize this ...

<xsl:apply-templates select="xmlout[(PERIOD=$pper and $pfieldname=$pplnt)]" mode="body">

... with $pfieldname representing the text PLANT_CODE, then it all stops working. I have tried adding quote marks but this also doesn't work.

So my big question now is: Am I trying to ask too much of XSL? Or am I approaching the problem in the wrong way?

If I can't parameterize the selection of field names like this, then it will mean that I have to build almost identical XSL templates over and over again. Arrgghh!

Maybe I have just misunderstood and XSL has a special way of doing this? I hope so.

Any tips would really help me on this one.

Regards,
Alan Searle.

Success! Sort of ...

It's probably not how it is supposed to be done but I have incorporated a variable which, when requeried (with javascript), flips the 'apply-templates' clause (using xsl:when). It is not exactly what I wanted but it sort of works (although speed is a bit sluggish).

Anyway, I'll do more experimenting and will report back to the forum.

Regards,
Alan.

XSLT is not a macro language. Variable represent values, not bits of text that you can substitute textually into an expression. If you have a value 3 or "London" in an expression like [x = 3] or [x = "London"] then you can replace the value with a variable reference. In these examples you can also replace x with a variable $X, but if the value of $X is "x", then you are doing a quite different test: instead of testing whether the element x is equal to 3 or "London", you are testing whether the String "x" is equal to 3 or London (which it isn't).

Similarly if you write X/$Y (which is actually allowed in XPath 2.0), and the value pf $Y is "fred", then this is the same as writing X/"fred", not the same as X/fred.

To replace an element name by a variable that holds the element name, change X/Y to X/*[name()=$VAR].

Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference

Hi Michael,

Thanks for your general comments: They prompted me to return to the books and to 'mug up' on the logic. That helps a lot.

> To replace an element name by a variable that holds the element
> name, change X/Y to X/*[name()=$VAR].

This snippet of syntax really got me moving: Now I can start flipping my display much more efficiently. Fantastic!

Thanks very much.

Regards,
Alan.