Position() and Issues with the value I am retrieving - xslt

<tableLayout>
<tableColumn width="250"/>
<tableDivider spaceAfter="0" spaceBefore="0"/>
<tableColumn/>
<tableDivider spaceAfter="0" spaceBefore="0"/>
<tableColumn/>
</tableLayout>
When selecting the width for the current "column" using the above data (not my decision to structure it like this) I am running into some issues.
<xsl:attribute name="style">
<xsl:text>width: </xsl:text>
<xsl:value-of select="../../tableLayout/tableColumn[position()]/#width" />
<xsl:text>px;</xsl:text>
</xsl:attribute>
This is how I am accessing the "current width" for the columns I am constructing. Fairly straightforward in my opinion. If I put [1] instead of the call to position, it returns 250 for each column. If I put [2] or [3] it returns nothing. [4] causes an error as it should.
If I print position() I see 1, 2 and 3.
But when it's accessing the data through this method, I get 250 each time. Is this something wrong on what I'm doing or a issue with XSL?

The position() is relative to the wrong context (it is relative to the [] context, not your XSLT context node). Try this:
<xsl:variable name="position" select="position()" />
<xsl:value-of select="../../tableLayout/tableColumn[$position]/#width" />

Related

XSLT/Xpath: How to find out that something is or isn´t in key (with if)?

I have problem with my code in XSLT with if. I am using key function and there I find out if something is in the key or not.
<xsl:key name="hlp" match="help" use="#id" />
...
<xsl:if test="key('hlp', #some_id) !=''">
...
</xsl:if>
That is correct it gives me what I want but how I can make opposite condition that #some_id isn´t in key hlp... I mean:
<xsl:if test="key('hlp', #some_id) <!--is equal--> ''">
...
</xsl:if>
Is there something like that in XSLT/XPath?
When you call key('x', 'y'), the result is the set of nodes in which the key is equal to 'y'. You can test whether a node-set is empty using the empty() function (in XSLT 2.0) or the not() function in XSLT 1.0:
<xsl:if test="not(key('x', 'y'))" version="1.0">...</xsl:if>
<xsl:if test="empty(key('x', 'y'))" version="2.0">...</xsl:if>
or for the inverse test (to test if something was found):
<xsl:if test="key('x', 'y')" version="1.0">...</xsl:if>
<xsl:if test="exists(key('x', 'y'))" version="2.0">...</xsl:if>
Testing by comparing the result against a string is wrong. The tests key('x','y')='' and key('x','y')!='' will both return false if the result of the key() function is an empty node-set; conversely, if the key() function selects two nodes, one with content and the other without, then both tests will return true.
<xsl:key name="hlp" match="help" use="#id" />
...
<xsl:if test="key('hlp', #some_id) !=''">
...
</xsl:if>
As already pointed by Michael Kay, avoid using the != operator unless truly knowing what it does.
This aside (and the fact that the key() function returns a node-set), it is more in the spirit of XSLT to write the above as:
<xsl:apply-templates select="key('hlp', #some_id)"/>
but how I can make opposite condition that #some_id isn´t in key
hlp... I mean:
<xsl:if test="key('hlp', #some_id) <!--is equal--> ''">
...
</xsl:if> ```
Is there something like that in XSLT/XPath?
Again, in the spirit of XSLT I recommend using code like this:
<xsl:apply-templates select="/*[not(key('hlp', #some_id))]" mode="not-found"/>
In the select expression above one can substitute /* with any existing node in the document -- if this really matters.

Looping through an xpath getting the right iteration each time in xslt 2

I have a condition where I need to loop atleast once and so I have the following xsl code. However, this doesnt work as it always gets the last iterations value. How can I tweak this so it gets the right iteration on each loop?
<xsl:variable name='count0'>
<xsl:choose>
<xsl:when test='count($_BoolCheck/BoolCheck[1]/CheckBoolType) = 0'>
<xsl:value-of select="1"/>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select='count($_BoolCheck/BoolCheck[1]/CheckBoolType)'/>
</xsl:otherwise>
</xsl:choose>
</xsl:variable>
<xsl:for-each select="1 to $count0">
<xsl:variable name='_LoopVar_2_0' select='$_BoolCheck/BoolCheck[1]/CheckBoolType[position()=$count0]'/>
<e>
<xsl:attribute name="n">ValueIsTrue</xsl:attribute>
<xsl:attribute name="m">f</xsl:attribute>
<xsl:attribute name="d">f</xsl:attribute>
<xsl:if test="(ctvf:isTrue($_LoopVar_2_0/CheckBoolType[1]))">
<xsl:value-of select=""Value True""/>
</xsl:if>
</e>
</xsl:for-each>
The xml file is as follows:
<BoolCheck>
<CheckBoolType>true</CheckBoolType>
<CheckBoolType>false</CheckBoolType>
<CheckBoolType>1</CheckBoolType>
<CheckBoolType>0</CheckBoolType>
<CheckBoolType>True</CheckBoolType>
<CheckBoolType>False</CheckBoolType>
<CheckBoolType>TRUE</CheckBoolType>
<CheckBoolType>FALSE</CheckBoolType>
</BoolCheck>
In this case I need to iterate through each iteration of CheckBoolType and produce a corresponding number of values. However, in the above example if there were no CheckBoolType iterations I would still like the iterations to enter the for-each loop atleast once. i hope that clarifies it a little more.
First observation: your declaration of $count0 can be replaced by
<xsl:variable name="temp" select="count($_BoolCheck/BoolCheck[1]/CheckBoolType)"/>
<xsl:variable name="count0" select="if ($temp=0) then 1 else $temp"/>
(Sorry if that seems irrelevant, but my first step in debugging code is always to simplify it. It makes the bugs much easier to find).
When you do this you can safely replace the predicate [position()=$count0] by [$count0], because $count0 is now an integer rather than a document node. (Even better, declare it as an integer using as='xs:integer' on the xsl:variable declaration.)
But hang on, $count0 is the number of elements being processed, so CheckBoolType[$count] will always select the last one. That's surely not what you want.
This brings us to another bug in your code. The value of the variable $_LoopVar_2_0 is an element node named CheckBoolType. The expression $_LoopVar_2_0/CheckBoolType[1] is looking for children of this element that are also named CheckBoolType. There are no such children, so the expression selects an empty sequence, so the boolean test is always false.
At this stage I would like to show you some correct code to achieve your desired output. Unfortunately you haven't shown us the desired output. I can't reverse engineer the requirement from (a) your incorrect code, and (b) your prose description of the algorithm you are trying to implement.

How can I shorten this XSLT snippet?

I have to repeat the following XSLT snippet like 100 times and I would like it to be as small as possible. Is there a way to make an equivalent XSLT snippet that is shorter?
<xslo:variable name="myVariable" select="//This/that/anotherthing" />
<xslo:choose>
<xslo:when test="string($myVariable) != 'NaN'">
<xslo:text>1</xslo:text>
</xslo:when>
<xslo:otherwise>
<xslo:text>0</xslo:text>
</xslo:otherwise>
</xslo:choose>
I'm basically setting the state of a checkbox based on whether or not a value exists in //This/that/anotherthing in the source xml.
Can be XSLT 1.0 or XSLT 2.0, doesn't matter.
You can use an if instead of xsl:choose (XSLT 2.0 only)...
<xsl:value-of select="if (string(number(//This/that/anotherthing)) = 'NaN') then 0 else 1"/>
I also dropped the xsl:variable, but if you need it for some other reason, you can put it back.
You could also create a function...
<xsl:function name="local:isNumber">
<xsl:param name="context"/>
<xsl:value-of select="if (string(number($context)) = 'NaN') then 0 else 1"/>
</xsl:function>
usage...
<xsl:value-of select="local:isNumber(//This/that/anotherthing)"/>
<xslo:variable name="myVariable" select="//This/that/anotherthing" />
<xslo:value-of select="number(boolean($myVariable))"/>
If I understand the purpose correctly - that is return 1 if the value in question can be successfully expressed as a number, 0 otherwise - then I believe:
<xsl:value-of select="number(//This/that/anotherthing castable as xs:double)"/>
would be the most straightforward way (in XSLT 2.0) to achieve it.
Edit
In view of your change of purpose:
I'm basically setting the state of a checkbox based on whether or not
a value exists in //This/that/anotherthing
That's even simpler:
<xsl:value-of select="number(boolean(string(//This/that/anotherthing)))"/>

Change text of elements identified by dynamic XPath

I have an XML with 2 XML fragments, 1st one is a fragment where the new values must be applied (which can have pretty complex elements) like
... some static parents
<a:element1>
<a:subelement tag="someString">
<a:s1>a</a:s1>
</a:subelement>
</a:element1>
<a:element2>b</a:element2>
<a:element3>c</a:element3>
... lots of other elements like the above ones
and 2nd fragment that has XPaths generated from the first XML and a new value, like
<field>
<xpath>/Parent/element1/subelement[#tag="someString"]/s1</xpath>
<newValue>1</newValue>
</field>
<field>
<xpath>/Parent/element2</xpath>
<newValue>2</newValue>
</field>
We might not have new values to apply for all the elements in the first fragment.
I'm struggling to make an XSLT transformation that should apply the new values to the places indicated by the XPaths.
The output should be:
... some static parents
<a:element1>
<a:subelement tag="someString">
<a:s1>1</a:s1>
</a:subelement>
</a:element1>
<a:element2>2</a:element2>
... lots of other elements like the above ones
I have access to xalan:evaluate to evaluate the dynamic xpath. I'm trying different solutions, I will write them here when they will start to make sense.
Any ideas of approaches are well received. Thanks
Oki, I found out how, and I will write the answer here maybe someone sometime will need this:
<xsl:template match="/">
<!-- static parents -->
<a:Root>
<xsl:apply-templates select="/a:Root/a:Parent" />
</a:Root>
</xsl:template>
<xsl:template match="#*|*|text()">
<xsl:variable name="x" select="generate-id(../.)" />
<xsl:variable name="y" select="//field[generate-id(xalan:evaluate(xpath)) = $x]" />
<xsl:choose>
<xsl:when test="$y">
<xsl:value-of select="$y/newValue" />
</xsl:when>
<xsl:otherwise>
<xsl:copy>
<xsl:apply-templates select="#*|*|text()" />
</xsl:copy>
</xsl:otherwise>
</xsl:choose>
</xsl:template>
And to explain the transformation:
I'm writing down part that is static and then call apply-templates on the fragment I'm interested in, that has a liquid structure.
Then I'm using a slightly modified identity transformation that copies everything from source to target (starting from the /a:Root/a:Parent fragment), except when we position ourselves on the text I'm interested in changing.
The text() I'm interested in will have as parent (../.) the element referred by an xpath string found in the second fragment. Variable x means, in the context of the when, this element.
Variable y finds a field element that has as child an xpath element that if evaluated using xalan will refer to the same element that the x variable relates to.
Now I used generate-id() in order to compare the physical elements, otherwise it would have compared by the toString of the element (which is wrong). If variable y doesn't exist, it means that I have no xpath element for this element that could have changed, and I'm leaving it alone. If the y variable exists, I can get from it the newValue and I'm currently positioned on the element which text I want to update.

XSLT Date Comparisons

<xsl:variable name="date1" select="2011-10-05"/>
<xsl:variable name="date2" select="2011-10-05"/>
<xsl:variable name="date3" select="2011-10-06"/>
<xsl:if test="$date2 = $date1 or $date2 < $date1">
..do something
</xsl:if>
<xsl:if test="$date3 = $date1 or $date3 > $date1">
.. do something
</xsl:if>
Both should evaluate true, but the second if doesn't. For the life of me I can't comprehended why!
In the actual transform the dates themselves are being drawn from an XML document but debugging through VS2010 i can see the values are as above.
Must be something fairly fundamental i'm doing wrong - any help would be brilliant!
I tried this in Oxygen/XML... select="2011-10-05 is being interpreted as an arithmetic expression, giving the value 1996 (2011 minus 10 minus 5) and "2011-10-06" is intrepreted as 1995.
What you want is
<xsl:variable name="date1" select="'2011-10-05'"/>
<xsl:variable name="date2" select="'2011-10-05'"/>
<xsl:variable name="date3" select="'2011-10-06'"/>
Note the extra single quotes.
From the XSLT 1.0 Specification:
If the variable-binding element has a select attribute, then the value
of the attribute must be an expression and the value of the variable
is the object that results from evaluating the expression.