MongoDB - PHP - Listing Collections

MongoDB provides MongoDatabase class to get list of collections within selected database.

Syntax

// select a database
$db = $client->myDb;

$cursor = $db->listCollectionNames();

// iterate cursor to display names of collections
foreach ($cursor as $collection) {
  echo $collection . "<br/>"
}

Listing Collections

To get list of collections, we first need to connect to a database and then iterate collection names as shown below −

<?php
   require __DIR__ . '\vendor\autoload.php';
   try {
	  $uri = "mongodb://localhost:27017";
      // connect to mongodb
      $client = new MongoDB\Client($uri);
      echo "Connection to database successful.<br/>";
       // select a database
      $db = $client->myDb;

      $db->createCollection("mycol");

      $cursor = $db->listCollectionNames();

      // iterate cursor to display names of collections
      foreach ($cursor as $collection) {
         echo $collection . "<br/>";
      }
   } catch (MongoDB\Driver\Exception\Exception $e) {	   
      echo "Exception:", $e->getMessage(), "\n";
   }
?>

Output

Now, let's compile and run the above program to drop a collection from our database myDb.

On executing, the above program gives you the following output.

Connection to database successful.
mycol
sampleCollection