// Using mapWithKeys
$collection = collect([
[
'name' => 'John',
'department' => 'Sales',
'email' => 'john@example.com',
],
[
'name' => 'Jane',
'department' => 'Marketing',
'email' => 'jane@example.com',
]
]);
$keyed = $collection->mapWithKeys(function ($item, $key) {
return [$item['email'] => $item['name']];
});
$keyed->all();
/*
[
'john@example.com' => 'John',
'jane@example.com' => 'Jane',
]
*/