Patch REST API to Partial Update MongoDB in .NET

Question

I have an object

{
  \"_id\": \"testobject\",
  \"A\": \"First line\",
  \"B\": \"Second line\",
  \"C\": \"Third line\"
}

I want to send a RE

Answer 1

You can use

IMongoUpdate updateDoc = new UpdateDocument("$set", doc);
collection.Update(Query.EQ("_id",id), updateDoc);

However, you should be careful.

If you first deserialize your document into SomeObject, all of the fields will get their default value (null for strings, 0 for ints etc). And if you use that object for the update, the fields that didn't exist in your json string would be updated to their default value.

If you use

var bsonDoc = BsonSerializer.Deserialize(jsonString);  
IMongoUpdate updateDoc = new UpdateDocument("$set", bsonDoc);
collection.Update(Query.EQ("_id",id), updateDoc);

your document on the database will be updated only for the fields that are present in your jsonString