Yup I'd do the contains thing, remembering to concat with necessare commas where appropriate.

First a couple of variables right after the currentPage parameter

<xsl:variable name="sectionNodeId" select="$currentPage/ancestor-or-self::node[@nodeTypeAlias='section']/@id" />
<xsl:variable name="resourceDocs" select="umbraco.library:GetXmlNodeById('resourceRootNodeId')" />

Here I'm assuming that the current page can be a descendant of a section-node in your content tree, and that the resource docs is located beneath a containing node with a hardcodable id (resourceRootNodeId).

Then an apply-templates statement in the main match section (you can do this with a for-each if you prefer)

<xsl:apply-templates select="$resourceDocs/node[contains(concat(',',./data[@alias='sectionIds']), concat(',',$sectionNodeId,','))]" />

Here I'm assuming the property with the multiple picker datatype is called sectionIds, the output will be a list of Id's separated with a comma, but with no preceding comma, so I've added a comma to the start of the sectionid list, to be sure I get no false positives., the second argument to the contains likewise holds the id of the section with commas around it to eliminate false positives.

Regards
Jesper Hauge

Thanks Lee and Jesper.  Jesper, that was exactly the way I thought about tackling it (I still might do it this way).  Lee, that's the other way - I thought it might be possible to split the CSV field into their own node-set but had no idea how to do this - very useful, your blog!

Thanks both!

Hi every one i have ultimate picker name (selected bebefits and the alise name selectTheBenefits it hold the data) but in reply i did not get nothing. The code are below. I user the this link code (leekelleher.com/.../#comment-619)

System.Xml.XmlException: The 'xsl:stylesheet' start tag on line 3 position 2 does not match the end tag of 'xsl:output'. Line 37, position 15. 
at System.Xml.XmlTextReaderImpl.Throw(Exception e) 
at System.Xml.XmlTextReaderImpl.Throw(String res, String[] args) 
at System.Xml.XmlTextReaderImpl.ThrowTagMismatch(NodeData startTag) 
at System.Xml.XmlTextReaderImpl.ParseEndElement() 
at System.Xml.XmlTextReaderImpl.ParseElementContent() 
at System.Xml.XmlTextReaderImpl.Read() 
at System.Xml.Xsl.Xslt.XsltInput.ReadNextSibling() 
at System.Xml.Xsl.Xslt.XsltInput.MoveToNextSibling() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadInstructions(List`1 content, InstructionFlags flags) 
at System.Xml.Xsl.Xslt.XsltLoader.LoadContent(Boolean hasSelect) 
at System.Xml.Xsl.Xslt.XsltLoader.XslVarPar() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadGlobalVariableOrParameter(NsDecl stylesheetNsList, XslNodeType nodeType) 
at System.Xml.Xsl.Xslt.XsltLoader.LoadRealStylesheet() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadDocument() 
at System.Xml.Xsl.Xslt.XsltLoader.LoadStylesheet(XmlReader reader, Boolean include)

The above error show. then i modify after that no result come. Please help me. to seperate the value from ultimate picker check box list. Thank you.

xsl:stylesheet [  ]>
<xsl:stylesheet 
  version="1.0" 
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform" 
  xmlns:msxml="urn:schemas-microsoft-com:xslt" 
  xmlns:umbraco.library="urn:umbraco.library" xmlns:Exslt.ExsltCommon="urn:Exslt.ExsltCommon" xmlns:Exslt.ExsltDatesAndTimes="urn:Exslt.ExsltDatesAndTimes" xmlns:Exslt.ExsltMath="urn:Exslt.ExsltMath" xmlns:Exslt.ExsltRegularExpressions="urn:Exslt.ExsltRegularExpressions" xmlns:Exslt.ExsltStrings="urn:Exslt.ExsltStrings" xmlns:Exslt.ExsltSets="urn:Exslt.ExsltSets" xmlns:PS.XSLTsearch="urn:PS.XSLTsearch" 
  exclude-result-prefixes="msxml umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings Exslt.ExsltSets PS.XSLTsearch ">

<xsl:output method="xml" omit-xml-declaration="yes"/>

<xsl:param name="currentPage"/>

<xsl:template match="/">

<xsl:variable name="preNodes">
<xsl:variable name="relatedContent" select="$currentPage/*[@id=1098]/*[@alias='selectTheBenefits']" />
<xsl:variable name="nodeIds" select="umbraco.library:Split($relatedContent, ',')" />
<xsl:for-each select="$nodeIds/value">

  <textarea>
    <xsl:copy-of select="$relatedContent" />
textarea>
<xsl:copy-of select="umbraco.library:GetXmlNodeById(.)"/>
xsl:for-each>
xsl:variable>
<xsl:variable name="nodes" select="msxml:node-set($preNodes)/node" />

<xsl:if test="count($nodes) > 0">

<div class="related-content">
<h3>Related Contenth3>
<ul>
                    <xsl:for-each select="$nodes">
    <li>
                            <a href="{umbraco.library:NiceUrl(@id)}">
                                <xsl:value-of select="@nodeName">
                            xsl:value-of>a>li>
xsl:for-each>ul>
div>

xsl:if>

xsl:template>

xsl:stylesheet>

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