(mongodb >=1.0.0)
MongoDB\Driver\Cursor::setTypeMap — Sets a type map to use for BSON unserialization
$typemap
   )Sets the type map configuration to use when unserializing the BSON results into PHP values.
typeMap (array)No value is returned.
Example #1 MongoDB\Driver\Cursor::setTypeMap() example
<?php
$manager = new MongoDB\Driver\Manager("mongodb://localhost:27017");
$bulk = new MongoDB\Driver\BulkWrite;
$id = $bulk->insert(['x' => 1]);
$manager->executeBulkWrite('db.collection', $bulk);
$query = new MongoDB\Driver\Query(['_id' => $id]);
$cursor = $manager->executeQuery('db.collection', $query);
$cursor->setTypeMap(['root' => 'array']);
foreach ($cursor as $document) {
    var_dump($document);
}
?>
The above example will output something similar to:
array(2) {
  ["_id"]=>
  object(MongoDB\BSON\ObjectID)#6 (1) {
    ["oid"]=>
    string(24) "56424fb76118fd3267180741"
  }
  ["x"]=>
  int(1)
}