（XML）PHP没有重命名所有标签？

Question

I have a problem... I want to rename the tags in some XML files. An it works with this code:

$xml = file_get_contents('data/onlinekeystore.xml');
renameTags($xml, 'priceEUR', 'price', 'data/onlinekeystore.xml');

But if I want to rename another XML file it doens't work with the SAME method... See the example below. I have no idea why... Does anybody has an idea and can help me?

$xml = file_get_contents('data/g2a.xml');
renameTags($xml, 'name', 'title', 'data/g2a.xml');

Function Code:

function renameTags($xml, $old, $new, $path){
    $dom = new DOMDocument();
    $dom->loadXML($xml);

    $nodes = $dom->getElementsByTagName($old);
    $toRemove = array();
    foreach ($nodes as $node) {
        $newNode = $dom->createElement($new);
        foreach ($node->attributes as $attribute) {
            $newNode->setAttribute($attribute->name, $attribute->value);
        }

        foreach ($node->childNodes as $child) {
            $newNode->appendChild($node->removeChild($child));
        }

        $node->parentNode->appendChild($newNode);
        $toRemove[] = $node;
    }

    foreach ($toRemove as $node) {
        $node->parentNode->removeChild($node);
    }

    $dom->saveXML();
    $dom->save($path);
}

onlinekeystore.xml Input:

<product>
    <priceEUR>5.95</priceEUR>
</product>

onlinekeystore.xml Ouput:

<product>
   <price>5.95</price>
</product>

g2a.xml Input:

<products>
    <name><![CDATA[1 Random STEAM PREMIUM CD-KEY]]></name>
</products>

g2a.xml Ouput:

<products>
    <name><![CDATA[1 Random STEAM PREMIUM CD-KEY]]></name>
</products>

Greetings

Answer 1

Consider a dynamic XSLT running the Identity Transform and then updates node names in a specific template anywhere in document. The sprintf formats XSL string passing in $old and $new values. This process avoids any nested looping through entire tree and even pretty prints output no matter the format of input.

function renameTags($xml, $old, $new, $path){
    // LOAD XML 
    $dom = new DOMDocument();
    $dom->loadXML($xml);

    // LOAD XSL
    $xslstr = '<xsl:transform xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
    <xsl:output version="1.0" encoding="UTF-8" indent="yes" method="xml" cdata-section-elements="%2$s"/>
    <xsl:strip-space elements="*"/>

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

      <xsl:template match="%1$s">
        <xsl:element name="%2$s">            
          <xsl:apply-templates/>
        </xsl:element>
      </xsl:template>

    </xsl:transform>';
    $xsl  = new DOMDocument();
    $xsl->loadXML(sprintf($xslstr, $old, $new));

    // INITIALIZE TRANSFORMER (REQUIRES php_xsl EXTENSION ENABLED IN .ini)
    $proc = new XSLTProcessor;
    $proc->importStyleSheet($xsl); 

    // TRANSFORM XML AND SAVE OUTPUT
    $newXML = $proc->transformToXML($dom);
    file_put_contents($path, $newXML);
}

Output

renameTags('<product><priceEUR>5.95</priceEUR></product>', 'priceEUR', 'price', 'data/onlinekeystore.xml');

// <?xml version="1.0" encoding="UTF-8"?>
// <product>
//   <price><![CDATA[5.95]]></price>
// </product>    

renameTags('<products><name><![CDATA[1 Random STEAM PREMIUM CD-KEY]]></name></products>', 'name', 'title', 'data/g2a.xml');

// <?xml version="1.0" encoding="UTF-8"?>
// <products>
//   <title><![CDATA[1 Random STEAM PREMIUM CD-KEY]]></title>
// </products>

Note: In XSLT, the <![CDATA[...]] tags are not preserved unless explicitly specified in <xsl:output>. Right now, any new node's text is wrapped with it. Remove the output spec and no CData tags render. So either include such escape tags for all or none.