使用for-each选择XML标记并将值放入XSLT中的不同标记中

Question

我的XML是 -

<doc>
<blk_customer_Details>
<custno>1010101</custno>
</blk_customer_Details>
<blk_customer_Details>
<custno>2020202</custno>
</blk_customer_Details>
<blk_customer_Details>
<custno>3030303</custno>
</blk_customer_Details>
</doc>

我的XSLT是 -

<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
<xsl:template match="/">
  <OPSC_IF_APPLICANT>
    <xsl:for-each select="blk_customer_Details">
        <xsl:variable name="counter" select="position()" />
        <xsl:copy>
         <xsl:choose>
        <xsl:when test="$counter = 1">
          <applicant_id><xsl:value-of select="custno"/></applicant_id>
        </xsl:when>
        <xsl:when test="$counter = 2">
         <applicant_id1><xsl:value-of select="custno"/></applicant_id1>
        </xsl:when>
        <xsl:when test="$counter = 3">
          <applicant_id2><xsl:value-of select="custno"/></applicant_id2>
        </xsl:when>
      </xsl:choose>
            </xsl:copy>
    </xsl:for-each>
   </OPSC_IF_APPLICANT>
</xsl:template>
</xsl:stylesheet>

我希望在应用XSLT后获得以下XML -

<OPSC_IF_APPLICANT>
<applicant_id>1010101</applicant_id>
<applicant_id1>2020202</applicant_id1>
<applicant_id2>3030303</applicant_id2>
</OPSC_IF_APPLICANT>

我是XSLT的新手。我已经看到了一些关于使用position（）函数的例子，我上面的XSLT应该可行。请让我知道我做错了什么。