替换xml远程文件中的值并保存[duplicate]

Question

This question already has an answer here:

• How do you parse and process HTML/XML in PHP? 30 answers

I have a remote xml file: http://my-site/my-file.xml This file has this values:

<files>

  <file>
     <unique>444444</unique>
  </file>
  <file>
     <unique>666666</unique>
  </file>
  <file>
     <unique>888888</unique>
  </file>

</files>

I need to use php to replace the value of <unique>xxxxxx</unique> to be half its value, so that the file should be change to

<files>

  <file>
     <unique>222222</unique>
  </file>
  <file>
     <unique>333333</unique>
  </file>
  <file>
     <unique>444444</unique>
  </file>

</files>

I got part of the function to open and save the file but not the find&replace code:

$xml_external_path = 'http://my-site/my-file.xml'; // THIS LINE MUST EXIST
$xml = simplexml_load_file($xml_external_path);// THIS LINE MUST EXIST

$searches = array();
$replacements = array();
foreach (....) {
    $searches[] = ....
    $replacements[] = ....
}
$newXml = simplexml_load_string( str_replace( $searches, $replacements, $xml->asXml() ) );

$newXml->asXml('new-xml.xml');// THIS LINE MUST EXIST

</div>

Answer 1

you can use preg_replace_callback for a pattern:

$txt = <<<XML
<?xml version='1.0'?>
<files>
  <file>
     <unique>444444</unique>
  </file>
  <file>
     <unique>666666</unique>
  </file>
  <file>
     <unique>888888</unique>
  </file>
</files>
XML;
// load the xml like a text
$xml_external_path = 'http://my-site/my-file.xml;'; 
$txt = file_get_contents($xml_external_path);

$pattern = '/<unique>(.*?)<\/unique>/';
$response = preg_replace_callback($pattern,function($match){
    $value = intval(trim($match[1]))/2;
    return '<unique>'.$value.'</unique>';
},$xml);

$newXml = simplexml_load_string( $response );//
$newXml->asXml('new-xml.xml');//create the xml

//print_r($newXml);