I'm working on a projects gallery which includes a number of drop down menus that filter the displayed projects.
It works very well, displaying 12 projects per page.

However if I filter my projects by "State" under the "All Locations" drop down and select "VIC" it appends the URL with "?state=VIC". But if I try to click onto page 2 of the VIC displayed projects I return no results even though there is a page there. The code for the pagination is removing the "?state=VIC" from the URL.

So I've tried adding "?state=<xsl:value-of select="projectState" />" to my pagination code, but the selected states value is not being passed into it.

Has anyone got any suggestions?
Cheers, JV

http://isis.brandtoolbox.com.au/projects/projects.aspx?state=VIC

ProjectsAlbum.xslt (code that displays the project gallery)

<?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:msxsl="urn:schemas-microsoft-com:xslt"
  xmlns:emint="urn:my-scripts"
  exclude-result-prefixes="msxml umbraco.library">
  <xsl:output method="xml" omit-xml-declaration="yes"/>

  <xsl:variable name="FF_projectList" select="umbraco.library:RequestForm('projects')" />
  <xsl:variable name="FF_projectTypeList" select="umbraco.library:RequestForm('projectType')" />
  <xsl:variable name="FF_projectLocationList_Temp" select="umbraco.library:RequestForm('projectLocation')" />
  <xsl:variable name="FF_sortType" select="umbraco.library:RequestForm('sortType')" />
  <xsl:variable name="FF_projectShowAll" select="umbraco.library:RequestForm('projectShowAll')" />
  <xsl:variable name="QS_projectLocationList" select="umbraco.library:RequestQueryString('state')" />
    
      <xsl:variable name="FF_projectLocationList">
      <xsl:choose>
        <xsl:when test="$QS_projectLocationList = ''"><xsl:value-of select='$FF_projectLocationList_Temp' /></xsl:when>
        <xsl:otherwise><xsl:value-of select='$QS_projectLocationList' /></xsl:otherwise>
      </xsl:choose>
    </xsl:variable>
    
  <xsl:param name="currentPage"/>
  <xsl:template match="/">
    
  
    
    <xsl:variable name="sectionId">
      <xsl:if test="($FF_projectList = 0 or $FF_projectList = '')">
        <xsl:value-of select="$currentPage/@id" />
      </xsl:if>
      <xsl:if test="($FF_projectList &gt; 0)">
        <xsl:value-of select="$FF_projectList" />
      </xsl:if>
    </xsl:variable>
    
    <input type="hidden" id="projectShowAll" name="projectShowAll" />

    <xsl:variable name="possibleNodes" select="$currentPage//* [@isDoc and string(./umbracoNaviHide) != '1' and name() != 'ProjectGallery' and name() = 'ProjectPage']" />
    <xsl:variable name="matchedNodesIdList">
      <xsl:for-each select="$possibleNodes" >
        <xsl:call-template name="projectNode">
          <xsl:with-param name="project" select="."/>
        </xsl:call-template>
      </xsl:for-each>
    </xsl:variable>
    <xsl:variable name="matchedNodes" select="$possibleNodes[contains($matchedNodesIdList, concat(@id, ';'))]" />

     <xsl:variable name="itemsPerPage">12</xsl:variable>
 <xsl:variable name="recordsPerPage">
   <xsl:choose>
     <xsl:when test="$FF_projectShowAll = 'true'">
       <xsl:value-of select="count($matchedNodes)" />
     </xsl:when>
     <xsl:otherwise>
       <xsl:value-of select="$itemsPerPage" />
     </xsl:otherwise>
   </xsl:choose>
    </xsl:variable>
    <xsl:variable name="pageNumber">
      <xsl:choose>
        <xsl:when test="umbraco.library:RequestQueryString('page') &lt;= 1 or string(umbraco.library:RequestQueryString('page')) = '' or string(umbraco.library:RequestQueryString('page')) = 'NaN'">1</xsl:when>
        <xsl:otherwise>
          <xsl:value-of select="umbraco.library:RequestQueryString('page')"/>
        </xsl:otherwise>
      </xsl:choose>
    </xsl:variable>
    <xsl:variable name="numberOfRecords" select="count($matchedNodes)"/>
    <xsl:value-of select="umbraco.library:RegisterStyleSheetFile('slider1', '/css/project_gallery.css')"/>
    <div id="project_gallery">
      <xsl:if test="$numberOfRecords = 0">
        <div id="projects_error_msg">
          <p>No projects with that search criteria were found.</p>
        </div>
      </xsl:if>
      <ul>
        <xsl:for-each select="$matchedNodes">
          <xsl:sort select="@nodeName[$FF_sortType = 'Client' or $FF_sortType='']"  order="ascending" />
          <xsl:sort select="completionDate[$FF_sortType = 'NewestToOldest' or $FF_sortType='']"  order="descending" />
          
          <xsl:sort select="./../@nodeName [$FF_sortType = 'Sector']"  order="ascending" />
          <xsl:if test="position() &gt; $recordsPerPage * number($pageNumber - 1) and position() &lt;= number($recordsPerPage * number($pageNumber - 1) + $recordsPerPage )">
            <li>
          <div id="project">
            <!-- get first photo thumbnail -->
            <a href="{umbraco.library:NiceUrl(@id)}">
              <xsl:if test="count(./* [@isDoc]) &gt; 0">
                <img src="{concat(substring-before(./*/projectImage,'.'), '_thumb_180.jpg')}"/>
              </xsl:if>     
              <xsl:if test="completionDate != ''">
                <h1><xsl:value-of select="umbraco.library:FormatDateTime(completionDate, 'MMMM yyyy')"/></h1>
              </xsl:if>
              <xsl:if test="projectClient != ''">
                <h2>
                  <!-- <xsl:value-of select="projectClient" /> -->
                  <xsl:value-of select="umbraco.library:StripHtml(pageTitle)" />
                </h2>
              </xsl:if>
              <xsl:if test="projectLocation != '' and projectState != ''">
                <p><xsl:value-of select="projectLocation" />,&nbsp;<xsl:value-of select="projectState" /></p>
              </xsl:if>
            </a>
          </div>
        </li>
          </xsl:if>
        </xsl:for-each>
      </ul>

      <xsl:if test="$numberOfRecords &gt; $recordsPerPage or $FF_projectShowAll != ''">
        <div id="page_numbers_nav">
          <xsl:if test="$numberOfRecords &gt; $recordsPerPage">
            <!--<xsl:if test="$pageNumber &gt; 1">
              <li>
                <xsl:call-template name="pageUrl">
                  <xsl:with-param name="pageNumber" select="$pageNumber - 1"/>
                  <xsl:with-param name="pageText" select="'previous'"/>
                  <xsl:with-param name="currentPageNumber" select="$pageNumber"/>
                  <xsl:with-param name="class" select="'previous'"/>
                  <xsl:with-param name="currentPageUrl">
                    <xsl:value-of select="umbraco.library:NiceUrl($currentPage/@id)" />?
                  </xsl:with-param>
                </xsl:call-template>
              </li>
            </xsl:if>-->

            <xsl:if test="$numberOfRecords &gt; $recordsPerPage">
              <xsl:call-template name="for.loop">
                <xsl:with-param name="i">1</xsl:with-param>
                <xsl:with-param name="page" select="$pageNumber"></xsl:with-param>
                <xsl:with-param name="count" select="ceiling(count($matchedNodes) div $recordsPerPage)"></xsl:with-param>
              </xsl:call-template>
            </xsl:if>



            <!--<xsl:if test="(($pageNumber) * $recordsPerPage) &lt; ($numberOfRecords)">
              <li>
                <xsl:call-template name="pageUrl">
                  <xsl:with-param name="pageNumber" select="$pageNumber + 1"/>
                  <xsl:with-param name="pageText" select="'next'"/>
                  <xsl:with-param name="currentPageNumber" select="$pageNumber"/>
                  <xsl:with-param name="class" select="'next'"/>
                  <xsl:with-param name="currentPageUrl">
                    <xsl:value-of select="umbraco.library:NiceUrl($currentPage/@id)" />?
                  </xsl:with-param>
                </xsl:call-template>
              </li>
            </xsl:if>-->
          </xsl:if>
          <xsl:variable name="currentUrl" select="umbraco.library:NiceUrl($currentPage/@id)" />

          <!-- Satjinder - Code for "SHOW ALL" function -->
   
            <xsl:choose>
              <xsl:when test="$FF_projectShowAll = ''" >
                <xsl:if test="$numberOfRecords &gt; $recordsPerPage">
                  <li class="show_all" id="showAll_Buttons">
                    <a>
                      <xsl:attribute name="href">
                        javascript:Projects_SetShowAll(true, '<xsl:value-of select="$currentUrl" />');
                      </xsl:attribute>
                      Show all&nbsp;&nbsp;<span><xsl:value-of select="$numberOfRecords"/></span>
                    </a>
                  </li>
                </xsl:if>
              </xsl:when>
              <xsl:otherwise>
                <li>
                  <a class="show_paged">
                    <xsl:attribute name="href">
                      javascript:Projects_SetShowAll(false, '<xsl:value-of select="$currentUrl" />');
                    </xsl:attribute>
                    Show paged
                  </a>
                </li>
              </xsl:otherwise>
            </xsl:choose>
          
          <!-- Close -->
        </div>
      </xsl:if>
    </div>

    <script type="text/javascript">

      function GotoNextPage(url)
      {
      //$("#searchImageClicked").val('search');
      document.forms[0].action=url;
      document.forms[0].submit();
      }

         function Projects_SetShowAll(flag, url){
             if (flag){
               $("#projectShowAll").val('true');
             }
             else{
               $("#projectShowAll").val('');
             }
             $("#aspnetForm").attr("action", url);
             $("#aspnetForm").submit();
         }
   
  </script>
  </xsl:template>

  <xsl:template name="for.loop">
    <xsl:param name="i"/>
    <xsl:param name="count"/>
    <xsl:param name="page"/>
    <xsl:if test="$i &lt;= $count">
      <li><xsl:if test="$page != $i">
        <xsl:call-template name="pageUrl">
          <xsl:with-param name="pageNumber" select="$i"/>
          <xsl:with-param name="pageText" select="$i"/>
          <xsl:with-param name="currentPageNumber" select="$page"/>
          <xsl:with-param name="class" select="'next_page'"/>
          <xsl:with-param name="currentPageUrl">
            <xsl:value-of select="umbraco.library:NiceUrl($currentPage/@id)" />?state=<xsl:value-of select="projectState" />
          </xsl:with-param>
        </xsl:call-template>
      </xsl:if></li>
      <xsl:if test="$page = $i">
        <span class="currentpage">
          <xsl:value-of select="$i" />
        </span>
      </xsl:if>
    </xsl:if>
    <xsl:if test="$i &lt;= $count">
      <xsl:call-template name="for.loop">
        <xsl:with-param name="i">
          <xsl:value-of select="$i + 1"/>
        </xsl:with-param>
        <xsl:with-param name="count">
          <xsl:value-of select="$count"/>
        </xsl:with-param>
        <xsl:with-param name="page">
          <xsl:value-of select="$page"/>
        </xsl:with-param>
      </xsl:call-template>
    </xsl:if>
  </xsl:template>

  <xsl:template name="projectNode">
    <xsl:param name="project"/>
    <xsl:variable name="projectLocationList"></xsl:variable>
    <xsl:if test="$projectLocationList =  $FF_projectLocationList">dd</xsl:if>
      <xsl:if test="((emint:SearchTerminValue2($project/projectType, $FF_projectTypeList) = 'true') and (emint:CompareIfValueIsThere1($project/projectState, $FF_projectLocationList, '/projects/projects.aspx') = 'true'))">
      <xsl:value-of select="$project/@id" />;
    </xsl:if>
  </xsl:template>

  <xsl:template name="pageUrl">
    <xsl:param name="pageNumber" select="1"/>
    <xsl:param name="pageText" select="1"/>
    <xsl:param name="class" select="page" />
    <xsl:param name="currentPageNumber" select="1"/>
    <xsl:param name="currentPageUrl" select="''"/>
    <a>
      <xsl:attribute name="class">
        <xsl:value-of select="$class" />
      </xsl:attribute>
      <xsl:attribute name="href">
      javascript:GotoNextPage('<xsl:value-of select="$currentPageUrl"/>&amp;tid=<xsl:value-of select="$pageNumber"/>&amp;page=<xsl:value-of select="$pageNumber"/>');
      </xsl:attribute>
      <xsl:value-of select="$pageText"/>
    </a>
  </xsl:template>



  <msxsl:script language="C#" implements-prefix="emint">
    <![CDATA[
    
    
     public bool CompareIfValueIsThere(string term, string value)
        {
          if (string.IsNullOrEmpty(value))
          {
            return true;
          }
          if (value.ToUpper() == term.ToUpper())
          {
            return true;
          }
          return false;
        }

         public bool CompareIfValueIsThere1(string term, string value, string emptyValue)
        {
          if (string.IsNullOrEmpty(value))
          {
            return true;
          }
         if (value == emptyValue)
          {
            return true;
          }
          if (value.ToUpper() == term.ToUpper())
          {
            return true;
          }
          return false;
        }
  public bool SearchTerminValue(string value, string term)
          {
            string[] terms = term.Split('/');
            foreach (string item in terms)
            {
                bool found = SearchTerminValue1(value, item);
         if (!found)
                {
                    return false;
                }
            }
            return true;
        }

  public bool SearchTerminValue1(string value, string term)
          {
            string[] terms = term.Split(' ');
            foreach (string item in terms)
            {
                int ind = value.IndexOf(item, StringComparison.InvariantCultureIgnoreCase);
         if (ind >= 0)
                {
                    return true;
                }
            }
            return false;
        }


  public bool SearchTerminValue2(string value, string term)
          {
            string[] terms = term.Split(',');
            foreach (string item in terms)
            {
                int ind = value.IndexOf(item, StringComparison.InvariantCultureIgnoreCase);
         if (ind >= 0)
                {
                    return true;
                }
            }
            return false;
        }


   ]]>
  </msxsl:script>
</xsl:stylesheet>

ProjectsFilter.xslt (code that filters the project gallery)

<?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:variable name="FF_projectList" select="umbraco.library:RequestForm('projects')" />
<xsl:variable name="FF_projectTypeList" select="umbraco.library:RequestForm('projectType')" />
<xsl:variable name="FF_projectLocationList_Temp" select="umbraco.library:RequestForm('projectLocation')" />
<xsl:variable name="FF_sortType" select="umbraco.library:RequestForm('sortType')" />    
    
      <xsl:variable name="QS_projectLocationList" select="umbraco.library:RequestQueryString('state')" />
    
      <xsl:variable name="FF_projectLocationList">
      <xsl:choose>
        <xsl:when test="$QS_projectLocationList = ''"><xsl:value-of select='$FF_projectLocationList_Temp' /></xsl:when>
        <xsl:otherwise><xsl:value-of select='$QS_projectLocationList' /></xsl:otherwise>
      </xsl:choose>
    </xsl:variable>
    
    
<xsl:param name="currentPage"/>
<xsl:template match="/">

<!-- start writing XSLT -->
  
    <form action="#">
      <div id="project_gallery_filter">
      <fieldset>
  <select name="projects" id="projects"  >
       <option value="{umbraco.library:NiceUrl($currentPage/@id)}">All sectors</option>
          <xsl:for-each select="$currentPage/* [@isDoc]">
             <option value="{umbraco.library:NiceUrl(@id)}">
    <xsl:if test="$FF_projectList = ./@id">
                      <xsl:attribute name="selected">selected</xsl:attribute>
           </xsl:if>
              <xsl:value-of select="@nodeName"/>
            </option>
          </xsl:for-each>
        </select>
      </fieldset>
      <fieldset>
        <xsl:variable name="projectTypeList" select="umbraco.library:GetPreValues(1212)//preValue" />
        <select name="projectType" id="projectType"  onchange="document.getElementById('aspnetForm').submit()" >
          <option value="">All project types</option>
          <xsl:for-each select="$projectTypeList">
            <xsl:sort order="ascending" data-type="text" />
             <option value="{.}">
               <xsl:if test="$FF_projectTypeList = .">
                 <xsl:attribute name="selected">selected</xsl:attribute>
               </xsl:if>
              <xsl:value-of select="." />
            </option>       
          </xsl:for-each>
        </select>        
      </fieldset>
      
      <fieldset>
        <xsl:variable name="projectLocationList" select="umbraco.library:GetPreValues(1211)//preValue" />
        <select name="projectLocation" id="projectLocation"  >
          <option value="{umbraco.library:NiceUrl($currentPage/@id)}">All locations</option>
          <xsl:for-each select="$projectLocationList">
            <xsl:sort order="ascending" data-type="text" />
             <option value="{umbraco.library:NiceUrl($currentPage/@id)}?state={.}">
               <xsl:if test="$FF_projectLocationList = .">
                 <xsl:attribute name="selected">selected</xsl:attribute>
               </xsl:if>
              <xsl:value-of select="." />
            </option>       
          </xsl:for-each>
        </select>        
      </fieldset>
      
      <fieldset>
        <select name="sortType" id="sortType" onchange = "document.getElementById('aspnetForm').submit()" >
          <option value="">Sort by</option>
             <option value="NewestToOldest">
    <xsl:if test="$FF_sortType= 'NewestToOldest'">
                      <xsl:attribute name="selected">selected</xsl:attribute>
           </xsl:if>
    Newest To Oldest
      </option>
             <option value="Client">
    <xsl:if test="$FF_sortType= 'Client'">
                      <xsl:attribute name="selected">selected</xsl:attribute>
           </xsl:if>
    Client A-Z</option>
             <option value="Sector">
    <xsl:if test="$FF_sortType= 'Sector'">
                      <xsl:attribute name="selected">selected</xsl:attribute>
           </xsl:if>
    Sector</option>
           </select>        
      </fieldset>
      </div>
    </form>
  
  <script type='text/javascript'>
     $(document).ready(function(){
        $("#projects").change(function(){ 
            $("#aspnetForm").attr("action",$(this).val());
                $("#aspnetForm").submit();
         });
   $("#projectLocation").change(function(){ 
            $("#aspnetForm").attr("action",$(this).val());
                $("#aspnetForm").submit();
         });


      });
  </script>

  
</xsl:template>

</xsl:stylesheet>