recursive function

[mediamind]

Hi,

WHat i want to achieve:
get an (1) array of all the parent_id's.
example categorie id 107 has a parent_id (96) categorie 96 has a parent (50) and 50 has a parent of (0)

This what i have sofar:
function get_all_parents($id) {

$sql = mysql_query("SELECT parent_id FROM download_categorie WHERE id = $id");
$row=mysql_fetch_array($sql);
$pid = $row["parent_id"];
$parents[] = $pid;
echo $pid;
if ($pid > 0) {
$parents[] = get_all_parents($pid);
}
return $parents;
}

The echo $pid gives me the good results: 96500 (3 parent_id's of categorie 107 = 96 50 0)

$bla = get_all_parents($categorie_id); //107

$count = count($bla);
for ($e=0; $e<$count; $e++) {
echo "parent: " . $bla[$e] ."<br>";
}
This only gives me a result of 96 and array

96500
parent: 96
parent: Array

I think this means that i get an array inside an array, right?

How can i get all the results in 1 array??

Kind regards,
Gerry

[lawnmowerman]

Hi Gerry.

You'll need to either pass the $parents array to the function each time you call it OR define it as a global variable.

It would be cleaner code if you pass it, though.

Each time the function is called, $parents is initialized (it's a new local variable), and doesn't effect the other $parents variables in other instances of the function.

Hope this helps.

-Rich

[mediamind]

Hi Rich,

That did the trick, thanks...

I used the "global" sollution.

How would i use the "pass" sollution ??

THanks,
Gerry

[lawnmowerman]

In order to pass the variable to the next recursion is the same as passing any variable to a function. You would simply have a 2nd parameter passed to the get_all_parents() function called $parents:

function get_all_parents( $id, $parents ) {
blah blah blah
if( $pid > 0 ) {
$parents[] = get_all_parents( $pid, $parents );
}
return $parents;
}

Keep in mind that you can default a variable in a function prototype to a value is none is passed:

function get_all_parents( $id, $parents = NULL ) {
blah blah blah
}

-Rich