PHP连接mongodb的现代用法---使用Monogodb\Driver\Manager

<?php
/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2018/11/29
 * Time: 2:23
 */
//require("mongoconn.php");
$wenwa = new MongoDB\Driver\Manager('mongodb://localhost:27017');
$filter=['_id'=>['$gte'=>0]];
$options=array();
$query = new MongoDB\Driver\Query($filter,$options);
$rows = $wenwa->executeQuery('olddream.color',$query);
echo var_dump($rows);
$i=0;
foreach($rows as $v)
{
   ++$i;
}
echo $i;
?>