regex / XSLT：替换边界内的特定字符串[重复]

Question

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我不确定如何使用正则表达式执行以下操作：在edge tags（）中，检查是否type="highway.secondary"，如果是，则将所有速度值替换为40。

<edge id="-100396051#2" type="highway.unclassified">
        <lane id="-100396051#2_0" index="0"  speed="13.89">
            <param key="origId" value="100396051"/>
        </lane>
    </edge>
    <edge id="-101784374#0" type="highway.secondary">
        <lane id="-101784374#0_0" index="0"  speed="27.78" length="17.22" >
            <param key="origId" value="101784374"/>
        </lane>
        <lane id="-101784374#0_1" index="1" speed="29.98" length="17.22" >
            <param key="origId" value="101784374"/>
        </lane>
    </edge>

到目前为止我得到了这个：(?<=type="highway\.secondary")(speed)(?=edge)，但是找不到速度......谢谢！

Answer 1

输入：edges.xml

<edges>
  <edge id="-100396051#2" type="highway.unclassified">
        <lane id="-100396051#2_0" index="0"  speed="13.89">
            <param key="origId" value="100396051"/>
        </lane>
    </edge>
    <edge id="-101784374#0" type="highway.secondary">
        <lane id="-101784374#0_0" index="0"  speed="27.78" length="17.22" >
            <param key="origId" value="101784374"/>
        </lane>
        <lane id="-101784374#0_1" index="1" speed="29.98" length="17.22" >
            <param key="origId" value="101784374"/>
        </lane>
    </edge>
</edges>

STYLESHEET：change_speed.xsl

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

<xsl:output method="xml" encoding="utf-8" indent="yes"/>

<xsl:template match="@*|node()">
    <xsl:copy>
        <xsl:apply-templates select="@*|node()" />
    </xsl:copy>
</xsl:template>

<xsl:template match="@speed[../parent::edge and ../../@type='highway.secondary']">
    <xsl:attribute name="speed">
      <xsl:value-of select="'40'"/>
    </xsl:attribute>
</xsl:template>


</xsl:stylesheet>

OUTPUT：

$ xsltproc change_speed.xsl edges.xml 
<?xml version="1.0" encoding="utf-8"?>
<edges>
  <edge id="-100396051#2" type="highway.unclassified">
        <lane id="-100396051#2_0" index="0" speed="13.89">
            <param key="origId" value="100396051"/>
        </lane>
    </edge>
    <edge id="-101784374#0" type="highway.secondary">
        <lane id="-101784374#0_0" index="0" speed="40" length="17.22">
            <param key="origId" value="101784374"/>
        </lane>
        <lane id="-101784374#0_1" index="1" speed="40" length="17.22">
            <param key="origId" value="101784374"/>
        </lane>
    </edge>
</edges>

说明：

<xsl:template match="@*|node()">
    <xsl:copy>
        <xsl:apply-templates select="@*|node()" />
    </xsl:copy>
</xsl:template>

将递归复制所有节点和属性

<xsl:template match="@speed[../parent::edge and ../../@type='highway.secondary']">
    <xsl:attribute name="speed">
      <xsl:value-of select="'40'"/>
    </xsl:attribute>
</xsl:template>

当您到达名为speed的属性，其父节点名为edge并且具有值为type的属性highway.secondary时，请将此属性的值更改为40。