building a multi-dimensional array .

[ftrudeau]

Greetings, consider the following array, where each key is the idGroup

Array
(
    [10] => Array
        (
            [vchTitle] => Main group with id #10
            [idParent] => 0
        )
    [19] => Array
        (
            [vchTitle] => Sub-group with id #19
            [idParent] => 10
        )
    [33] => Array
        (
            [vchTitle] => Sub-sub-group with id #33
            [idParent] => 19
        )
    [43] = Array
        (
            [vchTitle] => Sub-group with id #43, no child
            [idParent] => 10
        )
    [17] => Array
        (
            [vchTitle] => Main group with id #17, no child
            [idParent] => 0
        )
)

what i need to do is rebuild this array, using a multidimensionnal structure, with the following basic rule: if the value of idParent is zero, then this is a main group, which is not part of a parent group, otherwize, it is a sub-group (or sub-sub-group, or sub-sub-sub...-group), which is part of the idParent, which relates to idGroup

im having a hard time traversing the returned results, and building the multi-dimensionnal array properlly.

Ultimetelly, the array would end up with something like :

Array
(
    [10] => Array
        (
            [vchTitle] => Main group with id #10
            [childs] => Array
                (
                    [19] => Array
                        (
                            [vchTitle] => Sub-group with id #19
                            [idParent] => 10
                            [childs] => Array
                                (
                                    [33] => Array
                                    (
                                        [vchTitle] => Sub-sub-group with id #33
                                        [idParent] => 19
                                        [childs] =>
                                    )
                                )
                            )   

                        )
                    [43] = Array
                        (
                            [vchTitle] => Sub-group with id #43, no child
                            [idParent] => 10
                            [childs] =>
                        )
                )
            )
    [17] => Array
        (
            [vchTitle] => Main group with id #17, no child
            [childs] =>
        )
)

You get idea (i hope) 🙂
Thanks for any pointers.

[ZibingsCoder]

I'm going to just pretend you're getting the info from a database so that you can see it "used". This isn't tested, and I have someone looking at it to make sure I didn't make a silly mistake in my logic...but, here ya go.

<?php

function sort_groups ( &$main, &$ordered )
{
	while ( $curr = current($main) )
	{
		if ( !key_exists($main['idGroup'], $ordered) )
		{
			if ( $main['idParent'] >= 0 )
			{
				if ( key_exists($main['idParent'], $ordered) )
				{
					$ordered[$main['idParent']]['children'][$main['idGroup']] = array (
						'idParent' => $main['idParent'],
						'vchTitle' => $main['vchTitle'],
						'children' => array()
					);
				}

				else
				{
					while ( $curr = current($ordered) )
					{
						sort_groups($main, $curr['children']);

						next($ordered);
					}
				}
			}

			else
			{
				$ordered[$main['idGroup']] = array (
					'vchTitle' => $main['vchTitle'],
					'children' => array()
				);
			}
		}

		else
		{
			//uncomment this if you want to overwrite repeat instances
		/*	$ordered[$main['idGroup']] = array (
				'vchTitle' => $main['vchTitle'],
				'children' => array()
			); */
		}

		next($main);
	}

	return(true);
}

$mainArray = array();
$tempArray = array();

//added "ASC" to the end to make sure we get parents first
$str = "SELECT * FROM `groups` ORDER BY `idParent` ASC";

$query = mysql_query($str);

while ( $row = mysql_fetch_array($query, MYSQL_ASSOC) )
{
	$tempArray[$row['idGroup']] = array (
		'idGroup'  => $row['idGroup'],
		'idParent' => $row['idParent'],
		'vchTitle' => $row['vchTitle'],
		'children' => array()
	);
}

reset ( $tempArray );

sort_groups ( $tempArray, $mainArray );

echo ( "<pre>" );
print_r ( $mainArray );
echo ( "</pre>" );

?>

🙂

[ftrudeau]

I appreciate your time and effort. Your post did gave me some ideas, and one of my collegue finally ended up with this piece of code, that works perfectly

function go_multi_sub($src,$childmap,$id) {
    // Get main record
    $out = array();
    $out = $src[$id];
    $out["childs"] = array();

// For each child we mapped, call ourself to build child's entry and child's childs entries.
if (is_array($childmap[$id])) {
    while ($child_id = array_shift($childmap[$id])) {
        //$out["childs"][$child_id] = $src[$child_id];
        $out["childs"][$child_id] = go_multi_sub($src,$childmap,$child_id);
    }
}

// Return array
return $out;
}


function go_multi($src) {
    // Build child map ($childmap)
    $tmp = $src;
    while (list($k,$v) = each($tmp)) {
        // id($k) is a child of id($v->"idParent")
        // check if there is a parent first
        if ($v["idParent"] == 0) continue;

    // there is a parent. add this record in parent's child records.
    if (!(is_array($childmap[$v["idParent"]]))) $childmap[$v["idParent"]] = array();
    array_push($childmap[$v["idParent"]],$k);
}

// Build multi-dimensionnal array
$tmp = $src;
$dst = array();
while (list($k,$v) = each($tmp)) {
    // Do we have a parent? Yes? Quit!
    if ($v["idParent"] != 0) continue;

    // No! Top record.
    $dst[$k] = go_multi_sub($src,$childmap,$k);
}

// Return array as a result
return $dst;
}