如何通过php在xml中删除按属性搜索的节点及其子节点

Question

My XML file is given below I'm using the xml as external file:

<?xml version="1.0"?>
<custscales>
    <custscale sclNo="1" type="lin">
        <scaleName>Custom Scale Lin</scaleName>
        <jsfunc>custLin</jsfunc>
    </custscale>
    <custscale sclNo="2" type="map">
        <scaleName>Custome Scale Map</scaleName>
        <jsfunc>custMap</jsfunc>
    </custscale>
    <custscale sclNo="3" type="pol">
        <scaleName>Custome Scale Pol</scaleName>
        <jsfunc>custPol</jsfunc>
    </custscale>
    <custscale sclNo="4" type="tbl1">
        <scaleName>Custome Scale Table</scaleName>
        <jsfunc>custTbl1</jsfunc>
    </custscale>
</custscales>

From the above xml file I just want to delete the node where sclNo ="4" I mean the node bellow should not be in file after save.

    <custscale sclNo="4" type="tbl1">
        <scaleName>Custome Scale Table</scaleName>
        <jsfunc>custTbl1</jsfunc>
    </custscale>

It is requested to give the example using simpleXML.

Answer 1

<?php

$doc = new DOMDocument; 
$doc->load('theFile.xml');

$thedocument = $doc->documentElement;

$list = $thedocument->getElementsByTagName('custscale ');


$nodeToRemove = null;
foreach ($list as $domElement){
  $attrValue = $domElement->getAttribute('sclNo');
  if ($attrValue == '4') {
    $nodeToRemove = $domElement; //will only remember last one- but this is just an example :)
  }
}

if ($nodeToRemove != null)
$thedocument->removeChild($nodeToRemove);

echo $doc->saveXML(); 
?>

As taken fom here

Answer 2

using simplexml :

$xml = simplexml_load_string($x); // assume XML in $x
$i = count($xml); 

for ($i; $i > 0; $i--) {   
    $cs = $xml->custscale[$i];
    if ($cs['sclNo'] == "4") unset($xml->custscale[$i]);
}

Answer 3

It is requested to give the example using simpleXML

This has been outlined in detail in Remove a child with a specific attribute, in SimpleXML for PHP .

The key point is that you assign the element you want to unset to a variable - eg $element - for example by querying the single or multiple nodes with an Xpath query ( standard example ) - and then unsetting it:

$element = $xml->xpath('/path/to/element/to[@delete = "true"]')[0];
unset($element[0]);

That is already it in simplexml. As you can see, this is really simple. A full example:

$xml = simplexml_load_string(<<<BUFFER
<path>
 <to>
   <element>
     <to delete="true" />
   </element>
 </to>
</path>
BUFFER;
);

$element = $xml->xpath('/path/to/element/to[@delete = "true"]')[0];
unset($element[0]);

$xml->asXML('php://output');

See it in action.