C# MongoDB driver - need simple code to read/query collection

Question

I am new to MongoDB and I am using the C# driver, version: v4.0.30319: using MongoDB.Bson; using MongoDB.Driver;

First sorry for this probably being a simple question and I am just not able to find what I need correctly with correct search terms to make this work.

For my project. I am able to connect to the DB, get a list of all the collections, and loop through one of the collections using ASYNC. The problem I am having is trying to find examples to work for simple things like count, limit, or to find/get specific records.

Most of the examples appear to be an older version then what I am using and all what I can find requires ASYNC.

Here is a function I have that is working and returning data.

I want to be able to have a function that works that will and return sub sets of data (using a query), get a count, and other simple things.

My data in the collection is:

_id
RocketRequestID  int
LoanRocketID     int
RequestDate      date
CreatedByID      int
RequestXML       string/xml doc

My function is:

 static async Task<int>MainAsync()
    {

        int CountRecords = 0;

        var client = new MongoDatabaseConnection().mongoConn();

        IMongoDatabase db = client.GetDatabase("Viper");

        var collection = db.GetCollection<BsonDocument>("RocketRequest");            

        using (IAsyncCursor<BsonDocument> cursor = await collection.FindAsync(new BsonDocument()))
        {                
            while (await cursor.MoveNextAsync())
            {
                IEnumerable<BsonDocument> batch = cursor.Current;
                foreach (BsonDocument document in batch)
                {
                    Console.WriteLine(document);
                    Console.WriteLine();
                }
            }
        }// end using

        return CountRecords;

    }// end async 

Again this is probably something simple and I apologize but appreciate any help you can give.

Answer 1

You could create an object to map to your collection:

public class RocketRequest
{
    public string Id { get; set; }
    public int RocketRequestID { get; set; }
    public int LoanRocketID { get; set; }

    public DateTime RequestDate { get; set; }

    public int CreatedByID { get; set; }

    public string RequestXML { get; set; }
}

Then try using Linq by adding the following using statement

using MongoDB.Driver.Linq;

You can then write simpler queries like (for example)

var collection = db.GetCollection<RocketRequest>("RocketRequest");   
var count = collection.AsQueryable<Employee>()
              .Count();