BsonValue and custom classes in MongoDB C# Driver

Redth picture Redth · Oct 11, 2011 · Viewed 9.1k times · Source

I'm trying to use $push in an update query in mongodb, with the c# driver.

The Update.Push(...) method requires a string name (that's fine), and a BsonValue to be 'pushed'. This is where I run into problems. I'm trying to push a non simple type to the field's array.

For example: { $push : { "arrayfield" : { "a" : 7, "b" : 12 } } }

This works fine in the Mongo console, but I can't figure out how to make my object into a BsonValue. I've tried BsonValue.Create(myObjectInstance) but that gives me an error saying the .NET type cannot be mapped to a BsonValue.

Am I missing something simple?

Answer

Andrew Orsich picture Andrew Orsich · Oct 11, 2011

I know two approaches:

  1. Update.PushWrapped<MyObject>("arrayfield", myObjectInstance); //c# driver >= 1.0

  2. Or convert your class to BsonValue yourself via ToBsonDocument() extension method.

    Update.Push("arrayfield", myObjectInstance.ToBsonDocument());