在foreach循环中循环的数组中添加item

Question

So I have a foreach loop which loops though an array of items. The checkIfSubCategorie() returns an array with new items.

I want to place all these items in the $subcategorien array. This works good. The problem is that those items don't go through the initial foreach loop. Is this possible and if yes, how?

foreach($subcategorien as $subcat) {

    //make array with all subcategorien
    $newarray = self::checkIfSubCategorie($subcat);

    if(is_array($newarray)) {
        foreach($newarray as $a) {

            // add item to subcategorien
            array_push($subcategorien, $a);
        }
    }
}

This is the $subcategorien array before the initial foreach loop:

array(2) {
  [0]=> string(3) "701"
  [1]=> string(3) "702"
}

var_dump of $newarray:

array(1) {
  [0]=> string(1) "8"
}
bool(false)

This is the $subcategorien array after the foreach loop:

array(3) {
  [0]=> string(3) "701"
  [1]=> string(3) "702"
  [2]=> string(1) "8"
}

The result should be:

array(3) {
  [0]=> string(3) "701"
  [1]=> string(3) "702"
  [2]=> string(1) "8"
  [3]=> string(1) "9"
}

Answer 1

What you are looking for is called recursive function. Something like:

function getCategoryChildren($categoryParentId, $categories = array()) {
    // TODO: query to get all the categories by their parents id
    while ($row = $stmt->fetch_assoc()) {
         $categories[] = $row['category_id'];
         $categories = getCategoryChildren($row['category_id'], $categories);
    }
    return $categories;
}

$allCategories = getCategoryChildren(0);