<xsl:template match="/">

<xsl:variable name="src" select="$currentPage" />
  
  <xsl:variable name="yArr">
    <xsl:for-each select="$src/* [local-name()='newsArticle']">
      <xsl:sort select="umbraco.library:FormatDateTime(displayDate,'yyyy')" />
      
      <xsl:value-of select="umbraco.library:FormatDateTime(displayDate,'yyyy')" />,
    xsl:for-each>
  xsl:variable>
  <xsl:variable name="uniqueYears" select="ucomponents.strings:RemoveDuplicateEntries($yArr,',')" />

  <select>
    <option value="*">select a yearoption>
    <xsl:for-each select="umbraco.library:Split($uniqueYears)/value" >
      <option value="{.}"><xsl:value-of select="." />option>
    xsl:for-each>
  select>
xsl:template>

the above should do something like you are asking, but is untested. 

EDIT: it obviously relies on one of the uComponents string functions to remove any duplicate entries

<select>
<xsl:for-each select="$currentPage/node [string(data [@alias='umbracoNaviHide']) = '1']">
    <!--<li>
        <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
        </a>
    </li>-->

  <option><xsl:value-of select="data [@alias = 'year']"/></option>
 

</xsl:for-each>
</select>

her eis my code i get al years bu ti need to get distict Year liek no repeat of Years

Max, you could load all the years into a variable and then unique-ify them as in my code above, or you could possibly extend yours by sorting by year, looping through and only adding the year if it is different from the previous one.

Something like again, this is untested:

<select>
<xsl:for-each select="$currentPage/node [string(data [@alias='umbracoNaviHide']) = '1']">
<!-- FIRST SORT BY YEAR -->
<xsl:sort select="data [@alias = 'year']" />
    <!--<li>
        <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
        </a>
    </li>-->
<!-- ONLY INSERT IF THE YEAR IS NOT THE SAME AS THE PREVIOUS -->
<xsl:if test="data [@alias = 'year']  !=  ./preceding-sibling::node[1]/data [@alias = 'year']">
  <option><xsl:value-of select="data [@alias = 'year']"/></option>
</xsl:if>


</xsl:for-each>
</select>

Personally, i would recommend the uComponents string function for removing the dupes

Hi Max,

Better you should write some custom xsltextension using .net coding which gives you distinct values. You may follow this example http://our.umbraco.org/forum/developers/api-questions/18836-Media-?p=1

Pnima

<select>
<xsl:for-each select="$currentPage/node [string(data [@alias='umbracoNaviHide']) = '1']">
<!-- FIRST SORT BY YEAR -->
<xsl:sort select="data [@alias = 'year']" />
    <!--<li>
        <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
        </a>
    </li>-->
<!-- ONLY INSERT IF THE YEAR IS NOT THE SAME AS THE PREVIOUS -->
<xsl:if test="data [@alias = 'year']  !=  ./preceding-sibling::node[1]/data [@alias = 'year']">
  <option><xsl:value-of select="data [@alias = 'year']"/></option>
</xsl:if>
  

</xsl:for-each>
</select>

this one works fine but it gets rid of the common Years like if i have 2 years 1975 , and another ndoe 1975 i want to show ontl 1 
this one gets rid of that one and shows the rest 

hi max

sorry, i am not sure i understand your comment:

are you saying that this is not deduping the years correctly, that it is removing the first one and showing the rest?

thanks

its removing the common ones and showing the rest 

sorry if this is a silly question:

have you added the line to sort the years?

<xsl:sort select="./data [@alias = 'year']" />

its DONE i did it here is the code Just for the reference

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE xsl:stylesheet [ <!ENTITY nbsp "&#x00A0;"> ]>
<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"
    exclude-result-prefixes="msxml umbraco.library Exslt.ExsltCommon Exslt.ExsltDatesAndTimes Exslt.ExsltMath Exslt.ExsltRegularExpressions Exslt.ExsltStrings Exslt.ExsltSets ">

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

<xsl:param name="currentPage"/>
<xsl:key  name="MyKey" match="node" use="data [@alias = 'year']"/>

<xsl:template match="/">


<!-- The fun starts here  $currentPage-->
<select>
<xsl:for-each select="$currentPage/node [string(data [@alias='umbracoNaviHide']) = '1' ][generate-id() = generate-id(key('MyKey', data [@alias = 'year'])[1])]">
    <!--<li>
        <a href="{umbraco.library:NiceUrl(@id)}">
            <xsl:value-of select="@nodeName"/>
        </a>
    </li>-->

 
 <!-- <option><xsl:value-of select="data [@alias = 'year'] [not(.=preceding::data [@alias = 'year'])]"/></option>-->

 <option><xsl:value-of select="data [@alias = 'year']"/></option>
 
 

</xsl:for-each>
</select>

</xsl:template>

</xsl:stylesheet>

hi max

glad you worked it out. i didn't even think of using keys - seems much more efficient

good job

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