如何在PHP数组的每个数组元素中放入不同的对象？

Question

I have two arrays, eg

$mainArray = array('a','b','c','d','e','f','g');

$subArray = it contains an array of objects eg

array( objec1, objec2, object3, object4) ...

within each of the objects, holds the value that matches one of the keys in the $mainArray.

my Question now is, how am i gonna match and put the correct objects to the mainArray, so that it should appear like this eg

$mainArray = array('a'=> array(object3,object2), 'b' => array(object4,object1));

Answer 1

$result = array();
foreach ($subArray as $obj) {
    if (!isset($result[$obj->keyOfMainArray])) {
        $result[$obj->keyOfMainArray] = array();
    }

    $result[$obj->keyOfMainArray][] = $obj;
}

Answer 2

Assuming val is your object 's property

$mainArray = array('a','b','c','d','e','f','g');
$subArray  = array(...);
$result    = array();

foreach($subArray as $object) {
    $result[$object->val][] = $object;
}

Example result

Array
(
    [a] => Array
        (
            [0] => stdClass Object
                (
                    [val] => a
                )

            [1] => stdClass Object
                (
                    [val] => a
                )

        )

    [b] => Array
        (
            [0] => stdClass Object
                (
                    [val] => b
                )

        )

)