Your First MongoDB, C# and .NET Core App/My C# and MongoDB Cheat Sheet

Download .NET core SDK

Setup you project and your console project

1. Select a folder
2. In the command line: 
   dotnet new console -o console
   dotnet add console package MongoDB.Driver
   cd console
   code console
3. vsoode will be opened

Your First Basic Program

Create a program.cs file:

namespace HelloWorld

{

    class Program

    {

        static void Main(string[] args)

        {

            Console.WriteLine("Hello World!");

        }

    }

}

Run the code:

dotnet run

Now add a document and write it

using MongoDB.Driver;

using MongoDB.Bson;

using MongoDB.Bson.Serialization.Attributes;

namespace MongoData

{

    class Program

    {

        static void Main(string[] args)

        {

            Console.WriteLine("Hello World!");

            var mongoClient = new MongoClient("MONGODB_URL");

            var mongoDatabase = mongoClient.GetDatabase("trial_db");

            var collection = mongoDatabase.GetCollection<TrialDoc>("trial_cl");

            TrialDoc trialDoc = new TrialDoc();

            trialDoc.BookName = "123";

            collection.InsertOne(trialDoc);

            Console.WriteLine("Done!");

        }

    }

   

    public class TrialDoc

    {

        [BsonId]

        [BsonRepresentation(BsonType.ObjectId)]

        public string? Id { get; set; }

        [BsonElement("Name")]

        public string BookName { get; set; } = null!;

        public int Price { get; set; }

        public string Category { get; set; } = null!;

        public string Author { get; set; } = null!;

    }

}

Add Read Operation: Find All

            var list = collection.Find(_ => true).ToList();

            foreach (var item in list) {

                Console.WriteLine(item.BookName);

            }

Add Read Operation: Specific Record

            var single = collection.Find(x => x.BookName == "123".ToString()).FirstOrDefault();

            Console.WriteLine(single.Id);

Update the record

            collection.ReplaceOne(x => x.Id == single.Id, new TrialDoc() {Id = single.Id, BookName = "456"}, new ReplaceOptions {IsUpsert = true});

Smarter update using findAndModify

var _client = new MongoClient();
var _database = _client.GetDatabase("users");
var counters = _database.GetCollection<BsonDocument>("counters");
var counterQuery = Builders<BsonDocument>.Filter.Eq("_id", "eventId");

var findAndModifyResult = counters.FindOneAndUpdate(counterQuery,
              Builders<BsonDocument>.Update.Set("web", "testweb"));

Aggregation Framework

            FilterDefinition<TrialDoc> filter =

                Builders<TrialDoc>.Filter.Eq(x => x.BookName, "123");

            ProjectionDefinition<TrialDoc> project = Builders<TrialDoc>

                .Projection.Include(x => x.BookName);

            var results = collection.Find(filter).Project(project).ToList();

            foreach (var item in results) {

                Console.WriteLine(item);

            }

Full Text Search

Don't forget to create a full text search index first

            var results_list = collection.Find(Builders<TrialDoc>.Filter.Text("123")).ToList();

            foreach (var item in results_list) {

                Console.WriteLine(item);

            }

GeoSpatial Stuff

using MongoDB.Driver.GeoJsonObjectModel;

#Add to document
public GeoJson2DCoordinates Location { get; set; } = null!;
trialDoc.Location = new GeoJson2DCoordinates(31.11, 19.12);

var keys = Builders<BsonDocument>.IndexKeys.Geo2DSphere("Location");
await collection.Indexes.CreateOneAsync(keys);