php二维数组差集

<?php
$array1 = [
    ['id' => 1, 'name' => 'Alice'],
    ['id' => 2, 'name' => 'Bob'],
    ['id' => 3, 'name' => 'Charlie']
];

$array2 = [
    ['id' => 2, 'name' => 'Bob'],
    ['id' => 3, 'name' => 'Charlie'],
    ['id' => 4, 'name' => 'David']
];

function arrayDiffByKeys($array1, $array2) {
    $diff = [];
    foreach ($array1 as $item1) {
        $found = false;
        foreach ($array2 as $item2) {
            if ($item1['id'] == $item2['id']) {
                $found = true;
                break;
            }
        }
        if (!$found) {
            $diff[] = $item1;
        }
    }
    return $diff;
}

$diffArray = arrayDiffByKeys($array1, $array2);
print_r($diffArray);
?>

<?php
function arrayDiffByKey($array1, $array2, $key) {
    $keys1 = array_column($array1, $key);
    $keys2 = array_column($array2, $key);
    $diffKeys = array_diff($keys1, $keys2);
    $diffArray = [];
    foreach ($diffKeys as $diffKey) {
        $diffArray[] = current(array_filter($array1, function($item) use ($diffKey, $key) {
            return $item[$key] == $diffKey;
        }));
    }
    return $diffArray;
}

$diffArray = arrayDiffByKey($array1, $array2, 'id');
print_r($diffArray);
?>