Create unlimited ul li tag from Fetch array (for list)

Question

I'm going to make an unlimited list using li and ul tags from my PDO array results (extracted)

my array:

Array ( [0] => Array ( [category_label] => catLevel4 [category_id] => 22 [category_owner] => 21 ) [1] => Array ( [category_label] => catLevel3 [category_id] => 21 [category_owner] => 20 ) [2] => Array ( [category_label] => catLevel2 [category_id] => 23 [category_owner] => 8 ) [3] => Array ( [category_label] => catLevel2 [category_id] => 24 [category_owner] => 8 ) [4] => Array ( [category_label] => catLevel2 [category_id] => 20 [category_owner] => 6 ) [5] => Array ( [category_label] => catLevel1 [category_id] => 6 [category_owner] => 0 ) [6] => Array ( [category_label] => catLevel1 [category_id] => 7 [category_owner] => 0 ) [7] => Array ( [category_label] => catLevel1 [category_id] => 8 [category_owner] => 0 ) ) 

I want to:

 catLevel1 catLevel2 catLevel3 catLevel4 catLevel1 catLevel1 catLevel2 catLevel2 

i made a function to convert:

 function getCategory($parentCategoryId,$data) { foreach($data as $row){if($row['category_owner']==$parentCategoryId){?> <li catId='<?php echo $row['category_id']?>'><a><?php echo $row['category_label'];?></a> <ul> <?php getCategory($row['category_id'],$data) ;?> </ul> </li> <?php };} } echo getCategory(0,$this->categorysList); 

this function is very good for me, but create a null <ul></ul> for all the elements!

I appreciate your help in building a standard function, D

Answer 1

You get null <ul> tags because you hardcode it without any checks and output at each iteration. Try something like this:

 <?php function getCategory($parentCategoryId, $data) { foreach ($data as $row) { if ($row['category_owner'] == $parentCategoryId) { $str .= ' <li catId="' . $row['category_id'] . '"><a>' . $row['category_label'] . '</a>' . "\n"; $res = getCategory($row['category_id'], $data); if ($res) { $str .= ' <ul>' . $res . '</ul> ' . "\n"; } $str .= ' </li>' . "\n"; } } return $str; } $str = getCategory(0, $data); echo $str; ?> 

So, you get the output as follows:

 <li catId="6"> <a> catLevel1</a> <ul> <li catId="20"> <a> catLevel2</a> <ul> <li catId="21"> <a> catLevel3</a> <ul> <li catId="22"> <a> catLevel4</a> </li> </ul> </li> </ul> </li> </ul> </li> <li catId="7"> <a> catLevel1</a> </li> <li catId="8"> <a> catLevel1</a> <ul> <li catId="23"> <a> catLevel2</a> </li> <li catId="24"> <a> catLevel2</a> </li> </ul> </li>