mongodb obtaining collection names c#

Question

I'm trying to obtain a list of all databases and the associated list of collections for a connection using Mongo C# Driver.

foreach (string database in server.GetDatabaseNames())
 {
  var db = client.GetDatabase(database);

  var col = ((MongoDatabase)db).GetCollectionNames();

   //Do something
    }

I'm able to obtain the list of databases but not the collection names. It doesn't get past

         ((MongoDatabase)db).GetCollectionNames();

What am I possibly missing?

Solution 1

MongoDB version 2.6

mongodb-csharp driver: 2.1.1

Try :

//user: root  pwd:pwd dbName:admin
  try
  {
    var client = new MongoClient("mongodb://root:pwd@localhost/admin");
    var db = client.GetDatabase("admin");
    foreach (var item in db.ListCollectionsAsync().Result.ToListAsync<BsonDocument>().Result)
     {
                Console.WriteLine(item.ToString());
     }
  } catch (Exception ex)
  {

    throw ex;
  }

Important: User 'root' must exists in the db

On cmd as admin

C:\yourMongoServer\bin>mongo.exe --port 27017
use admin
db.createUser(
  {
    user: "root",
    pwd: "pwd",
    roles: [ { role: "userAdminAnyDatabase", db: "admin" } ]
  }
)

Solution 2

This is how I have solved this problem, because the accepted answer hasn't worked for me.

MongoDb version 3.4.0.
C# Driver version 2.4.3.23.

public List<string> GetCollections()
{
    List<string> collections = new List<string>();

    foreach (BsonDocument collection in _database.ListCollectionsAsync().Result.ToListAsync<BsonDocument>().Result)
    {
        string name = collection["name"].AsString;
        collections.Add(name);
    }

    return collections;
}

Solution 3

MongoDB version: 3.4.6, C# Driver version: 2.4.4

Working Solution:

        using (IAsyncCursor<BsonDocument> dbCursor = client.ListDatabases())
        {
            while (dbCursor.MoveNext())
            {
                foreach (var dbDoc in dbCursor.Current)
                {
                    Console.WriteLine("-----{0}-----", dbDoc["name"]);
                    var dbName = dbDoc["name"].ToString();  // list database name
                    using (IAsyncCursor<BsonDocument> collectionCursor = client.GetDatabase(dbName).ListCollections())
                    {
                        while (collectionCursor.MoveNext())
                        {
                            foreach (var collDoc in collectionCursor.Current)
                            {
                                Console.WriteLine(collDoc["name"]);  // list collection name
                            }
                        }
                    }
                }
            }
        }

Comments

[sandy]

this works:) I just had to use the line "db.ListCollectionsAsync().Result.ToListAsync<BsonDocument>(‌​).Result"

[Dmitry Gusarov]

you can just write ListCollections().ToList()

[Alan Clark]

Better to use non-async_database.ListCollections() instead of using Result.

[levilime]

item.ToString() gives not only the collection Name but also metadata. @VansFannel's answer is up to date and works correctly.

[JHBonarius]

why do you catch the exception just to throw it again?