How to check if collection exists in MongoDB using C# driver?

Question

Is there any way in C# to check if a collection with a specific name already exists in my MongoDB database?

Answer 1

You can do it like this:

database.GetCollection("blah").Exists()

Answer 2

@Ofir answer is correct. Here's a synchronous alternative built around the ListCollectionNames API:

public bool CollectionExists(IMongoDatabase database, string collectionName)
{
    var filter = new BsonDocument("name", collectionName);
    var options = new ListCollectionNamesOptions { Filter = filter };

    return database.ListCollectionNames(options).Any();
}

Answer 3

@im1dermike answer is no longer working for c# driver version 2.0+

Here is an alternative:

    public async Task<bool> CollectionExistsAsync(string collectionName)
    {
        var filter = new BsonDocument("name", collectionName);
        //filter by collection name
        var collections = await GetDatabase().ListCollectionsAsync(new ListCollectionsOptions { Filter = filter });
        //check for existence
        return await collections.AnyAsync();
    }