Comments on: Converting a flat array with Parent ID’s to a nested Tree

By: misz

misz — Tue, 15 Sep 2009 10:32:27 +0000

Hey, function works like a charm, but only if you have only 1 master item. If for example 2 items have parent = null, it returns only last branch of tree. I’ve achieved good results with:
//second pass
$root = null;
foreach ($indexed as $id => $row) {
$indexed[$row[$parentIdField]][$childNodesField][$id] =& $indexed[$id];
if ($row[$parentIdField] === null) {
$root = $id;
$roots[] = $id;
}
}

//Had to be modified, beacuse it returned only the last indexed root id
foreach ($roots as $k) {
$return[$k] = $indexed[$k];
}
return $return;

By: Brenton Alker

Brenton Alker — Thu, 07 May 2009 06:51:20 +0000

Good point, I can’t see any reason to look for NULL specifically. I’ve gone with a check for boolean false equivalents instead (mainly because empty was causing odd rendering issues and I’m too lazy to figure out why).

Updated again.

By: Sasa Tomislav Mataic

Sasa Tomislav Mataic — Wed, 06 May 2009 10:49:09 +0000

Hey, sweet function

I had one small problem though, my root node had ‘parentId’ = ‘0′, so when checking if ($row[$parentIdField] === null) it never finds the root node.

better solution may be like this
if (empty($row[$parentIdField]))

I know that === null is faster, but this way was more convenient for me.

Thanks a lot

By: Brenton Alker

Brenton Alker — Thu, 30 Apr 2009 12:47:35 +0000

Right you are. That’s what I get for “fixing” code without testing it.

Updated post.

By: Pavel Jirák

Pavel Jirák — Thu, 30 Apr 2009 12:16:57 +0000

hi,

may there is mistake, because item id = 4 has parentId = 1 not 3. Second problem is in return value of function. Index 0 isn’t in array.