Question

I have a PHP function called processDeleteForm() designed to remove a specified node from an xml document named structure.xml. The only problem I’m having with it so far is that in processDeleteForm(), it searches for the node to be removed by looping through each child node of the parent node, and matches it by the “name” attribute, but I haven’t been able to get the correct number of child nodes for the loop, so it stops before it reaches the correct node. Relevant code:

function processDeleteForm($dir, $filename)
{
  echo "Processing delete request.<br/>";
  echo "Request to delete ".$filename." from ".$dir.".<br/>";
  $xmlDoc = new DOMDocument();

  $xmlDoc->load("structure.xml");
  $node = dirDOMNodeWritable($dir, $xmlDoc);

  $target;
  echo "Working directory has ".count($node->childNodes)." child(ren).<br/>";
  for($x = 0; $x < count($node->childNodes); $x++)
  {
    if($node->childNodes->item($x)->getAttribute("name") == $filename)
    {
      $target = $node->childNodes->item($x);
      echo "Target found.<br/>";
    }
    else
    {
      echo "Searching for target...<br/>";
    }
  }

  if($target->getAttribute("type") != "directory")
  {
    $fstored = "uploads/".$target->childNodes->item(0)->wholeText;
    unlink($fstored);
  }

  $node->removeChild($target);

  $file = fopen("structure.xml", "w");
  fwrite($file, $xmlDoc->saveXML());

}

structure.xml:

<?xml version="1.0" encoding="ISO-8859-1"?>
<directory name="root" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="directory">
  <directory name="music" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="directory">
    <directory name="She" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="directory">
      <directory name="Chiptek" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="directory">
        <directory name="mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="directory">
          <file name="intro.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">intro.mp3</file>
          <file name="music.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">music.mp3</file>
          <file name="supersonic.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">supersonic.mp3</file>
          <file name="memories.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">memories.mp3</file>
          <file name="chiptek.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">chiptek.mp3</file>
          <file name="intermission.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">intermission.mp3</file>
          <file name="kicks.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">kicks.mp3</file>
          <file name="1997.mp3" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/mpeg">1997.mp3</file>
        </directory>
        <directory name="ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="directory">
          <file name="intro.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">intro.ogg</file>
          <file name="music.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">music.ogg</file>
          <file name="supersonic.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">supersonic.ogg</file>
          <file name="memories.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">memories.ogg</file>
          <file name="chiptek.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">chiptek.ogg</file>
          <file name="intermission.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">intermission.ogg</file>
          <file name="kicks.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">kicks.ogg</file>
          <file name="1997.ogg" owner="elarsen" read="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" write="aclum,ahoffman,apavlowski,bvollmer,dpotts,drichardson,epiatt,jcantrell,jreeve,kdouglas,kjab,lbrewer,lholliday,mfriedman,norty,pmoore,rlongwell,scatlett,sketcherside,tperkins" type="audio/ogg">1997.ogg</file>
        </directory>
      </directory>
    </directory>
  </directory>
  <directory name="test01" owner="elarsen" read="0" write="0" type="directory"/>
  <directory name="test02" owner="elarsen" read="0" write="0" type="directory"/>
  <directory name="test03" owner="elarsen" read="0" write="0" type="directory"/>
</directory>

*The above is supposed to be the contents of an xml file, but I can’t figure out how to display it as such. If somebody with more knowledge about formatting xml on stackoverflow could fix it, I would be much obliged.

It might also be useful to see the code responsible for the creation of the directories named “test01”, “test02”, and “test03”:

function processNewForm($dir, $dirName, $readPrivs, $writePrivs)
{
  $readString = "";
  $writeString = "";
  $dirOwner = $_SESSION["user"];

  for($x = 0; $x < count($readPrivs); $x++)
  {
    $readString += $readPrivs[$x].",";
  }
  for($x = 0; $x < count($writePrivs); $x++)
  {
    $writeString += $writePrivs[$x].",";
  }

  $xmlDoc = new DOMDocument();

  $xmlDoc->load("structure.xml");
  $node = dirDOMNodeWritable($dir, $xmlDoc);

  $newDir = $xmlDoc->createElement("directory");
  $newDir->setAttribute("name", $dirName);
  $newDir->setAttribute("owner", $dirOwner);
  $newDir->setAttribute("read", $readString);
  $newDir->setAttribute("write", $writeString);
  $newDir->setAttribute("type", "directory");

  $node->appendChild($newDir);

  $file = fopen("structure.xml", "w");
  fwrite($file, $xmlDoc->saveXML());

}

The current output looks like this:

Received delete request.
Validating delete request... Request is valid.
Processing delete request.
Request to delete test03/ from /.
Working directory has 1 child(ren).
Searching for target...

Notice: Undefined variable: target in E:\aepi\dev\fileshare.php on line 540

Fatal error: Call to a member function getAttribute() on a non-object in E:\aepi\dev\fileshare.php on line 540

Answer 1

From the PHP manual for count():

Returns the number of elements in var. If var is not an array or an object with implemented Countable interface, 1 will be returned.

DOMNode::$childNodes is a DOMNodeList object. It is not Countable. It will always return one (even if empty). Use its length property instead:

$count = $element->childNodes->length;

Update: DOMNodeList has been made Countable from PHP 7.2 onwards.