php - Combine external XML files into one and orderby -

i have following php function combine multiple external xml files 1 file:

<?php     function combinexml($file)      {          global $xmlstr;           $xml = simplexml_load_file($file);           foreach($xml $element)              $xmlstr .= $element->asxml();      }       $files[] = "file1.xml";      $files[] = "file2.xml";       $xmlstr = '<productitems>';      foreach ($files $file)          combinexml($file);       $xmlstr .= '</productitems>';       $xml = simplexml_load_string($xmlstr);      $bytes = file_put_contents("output.xml", $xml->asxml());     ?> 

is possible re-order feed? having last modified on top? order lastmodified file system date.

you did not provide xml examples let's assume simple structures:

$xmls = [  '<productitems>   <item>     <title>item 1</title>     <lastmodified>1</lastmodified>   </item> </productitems>', '<productitems>   <item>     <title>item 2</title>     <lastmodified>2</lastmodified>   </item> </productitems>' ]; 

merging xmls

i prefer using dom. (it's easier, because here no automagic mapping).

first create target document , add document element node:

$merged = new domdocument(); $merged->appendchild($merged->createelement('productitems')); 

next iterate xmls, load them doms , copy child nodes of document element target document.

foreach ($xmls $xml) {   $source = new domdocument();   $source->loadxml($xml);   foreach ($source->documentelement->childnodes $node) {     $merged->documentelement->appendchild(       $merged->importnode($node, true)     );   } } 

allow formatting , save merged xml:

$merged->formatoutput = true; echo $merged->savexml(); 

output:

<?xml version="1.0"?> <productitems>   <item>     <title>item 1</title>     <modified>1</modified>   </item>       <item>     <title>item 2</title>     <modified>2</modified>   </item> </productitems> 

working files

if you're working files have use domdocument::load() , domdocument::save(). domdocument::loadxml()/savexml() xml strings.

sorting nodes

fetch item nodes source document using xpath , convert node list array:

$xpath = new domxpath($merged); $products = iterator_to_array($xpath->evaluate('//item')); 

sort array using usort. using xpath, can fetch data in context of node:

usort(   $products,   function($nodeone, $nodetwo) use ($xpath) {     return strnatcmp(       $xpath->evaluate('string(modified)', $nodetwo),       $xpath->evaluate('string(modified)', $nodeone)     );       } ); 

create target document , copy nodes it:

$sorted= new domdocument(); $sorted->appendchild($sorted->createelement('productitems')); foreach ($products $node) {   $sorted->documentelement->appendchild(     $sorted->importnode($node, true)   ); }  $sorted->formatoutput = true; echo $sorted->savexml(); 

output:

<?xml version="1.0"?> <productitems>   <item>     <title>item 2</title>     <modified>2</modified>   </item>   <item>     <title>item 1</title>     <modified>1</modified>   </item> </productitems>