Incrementing and checking the counter variable in

2019-01-07 23:08发布

站内问答 / 后端开发
1865 6 5

I am having little difficulty in assigning a counter variable and incrementing it and then checking for a certain value in XSLT. Here is my code:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" <xsl:variable name="empty_string"/>
    <xsl:variable name="counter" select="0"/>
<xsl:template match="/Collection">
        <xsl:for-each select="Content">
            <xsl:sort select="Html/root/Event/start_date" order="ascending"/>
 <xsl:variable name="isFutureEvent">
                        <xsl:value-of select="syscom:isFutureDate(Html/root/Event/start_date)" />
                    </xsl:variable>

                    <xsl:if test="Html/root/Event != $empty_string">
                        <xsl:if test="$isFutureEvent='true'">
                            <!-- Increment Counter -->
                            <xsl:value-of select="$counter + 1"/>
                            <!-- Test if Counter < 4 -->
                            <xsl:if test="$counter &lt; 3">
                            <div class="media">
                            <!-- Do stuff here -->
                      </div>
                            </xsl:if>  <!-- End if for counter -->  
                        </xsl:if>
                    </xsl:if>
                <!--</xsl:when>-->
            <!--</xsl:choose>-->
        </xsl:for-each>
    </xsl:template>
</xsl:stylesheet>

But it doesnt seem to increment my counter and not exiting when the counter hits 3. Any help on this ?

标签： xml xslt
举报
6条回答
ゆ 、 Hurt°
2楼-- · 2019-01-07 23:20

If you want to know where you are in a for-each loop, you can use the built-in position() function. 

<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:template match="/Collection">
        <xsl:for-each select="Content">
            <xsl:if test="position() &lt; 3">
                <!-- Do this for nodes 1, 2 and 3 -->
            </xsl:if>
            <!-- Do this for every node -->
        </xsl:for-each>
    </xsl:template>
</xsl:stylesheet>
查看更多
0人赞 添加讨论(0) 举报
走好不送
3楼-- · 2019-01-07 23:21

'Variables' in XSL are actually constants - you cannot change their value. This:

<xsl:value-of select="$counter + 1"/>

will just output the value of $counter+1

To do loops you have to use recursion - e.g.:

<xsl:stylesheet 
  version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

  <xsl:template name="loop">
    <xsl:param name="i"/>
    <xsl:param name="limit"/>
    <xsl:if test="$i &lt;= $limit">
      <div>
        <xsl:value-of select="$i"/>
      </div>
      <xsl:call-template name="loop">
        <xsl:with-param name="i" select="$i+1"/>
        <xsl:with-param name="limit" select="$limit"/>
      </xsl:call-template>
    </xsl:if>
  </xsl:template>

  <xsl:template match="/">
    <html>
      <body>
        <xsl:call-template name="loop">
          <xsl:with-param name="i" select="0"/>
          <xsl:with-param name="limit" select="10"/>
        </xsl:call-template>
      </body>
    </html>
  </xsl:template>

</xsl:stylesheet>

altough it is better to try to avoid loops - in most cases the XSL can be written to avoid it, but I don't understand enough of what are you trying to achieve to give you the complete solution.

查看更多
0人赞 添加讨论(0) 举报
我命由我不由天
4楼-- · 2019-01-07 23:24

In case any one wants to do this while using .net (XslCompiledTransform) you can use

<xsl:stylesheet ...  xmlns:customCode="urn:customCode">

<msxsl:script language="VB" implements-prefix="customCode">
    <![CDATA[
    private mCounter As Integer
    Public Function AddToCounter() As Boolean
      mCounter += 1
      Return True
    End Function
    Public Function GetCounter() As Integer
      Return mCounter
    End Function
    ]]>
</msxsl:script>

Then you add a call to "customCode:AddToCounter()", and then you could write a message like this <xsl:message><xsl:value-of select="customCode:GetCounter()" /> rows remaining.</xsl:message>

查看更多
0人赞 添加讨论(0) 举报
该账号已被封号
5楼-- · 2019-01-07 23:35

I have same problem. I need increment value in loop. So the simplest way was include Saxon and use that value.

if you use Saxon 6.5.5

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
...
xmlns:saxon="http://icl.com/saxon"
extension-element-prefixes="saxon"
version="3.0">

if you use Saxon 9.4.0.4

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
...
xmlns:saxon="http://saxon.sf.net/"
extension-element-prefixes="saxon"
version="3.0">

And after that you can simply use saxon variable :

<xsl:variable name="counter" select="0" saxon:assignable="yes"/> <!-- declare value -->

<saxon:assign name="counter" select="$counter+1"/> <!-- increment value, you can do it in loop for example-->

<xsl:value-of select="$counter"></xsl:value-of> <!-- print value -->
查看更多
0人赞 添加讨论(0) 举报
Evening l夕情丶
6楼-- · 2019-01-07 23:38

In my case I needed total of boxes in the shipment, this helped

    <xsl:for-each select="ShippingConfirmation/Details/LicensePlates/LicensePlate">
            <xsl:if test="position()=last()">
                <xsl:value-of select="position()"/> 
            </xsl:if>
    </xsl:for-each>
查看更多
0人赞 添加讨论(0) 举报
聊天终结者
7楼-- · 2019-01-07 23:41

We cant update xsl:variable as they are just like constants. But we can updated dp:local-variables, so here dp:local-variable counter is initialized before starting for-loop. Each time loop is run counter will update itself by 1. Try This:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" <xsl:variable name="empty_string"/>
    <xsl:template match="/Collection">
        <dp:set-local-variable name="'counter'" value="0"/>
        <xsl:for-each select="Content">
            <dp:set-local-variable name="'counter'" value="dp:local-variable('counter')+1"/>
            <xsl:sort select="Html/root/Event/start_date" order="ascending"/>
            <xsl:variable name="isFutureEvent">
                <xsl:value-of select="syscom:isFutureDate(Html/root/Event/start_date)" />
            </xsl:variable>

            <xsl:if test="Html/root/Event != $empty_string">
                <xsl:if test="$isFutureEvent='true'">

                    <xsl:value-of select="dp:local-variable('counter')"/>
                    <!-- Test if Counter < 4 -->
                    <xsl:if test="dp:local-variable('counter') &lt; 3">
                        <div class="media">
                            <!-- Do stuff here -->
                        </div>
                    </xsl:if>
                    <!-- End if for counter -->  
                </xsl:if>
            </xsl:if>
            <!--</xsl:when>-->
            <!--</xsl:choose>-->
        </xsl:for-each>
    </xsl:template>
</xsl:stylesheet>
查看更多
0人赞 添加讨论(0) 举报
登录 后发表回答
相关问题
查看全部
相关文章
查看全部
收藏的人(5)