在MongoDB

Question

我是MongoDB的初学者。请参阅下面的模型。

public class Technology
{
    public Technology()
    {
        ProductGroups = new List<ProductGroup>();
    }

    [BsonRepresentation(BsonType.ObjectId)]
    public ObjectId _id { get; set; }

    public string Name { get; set; }

    public IEnumerable<ProductGroup> ProductGroups { get; set; }
}

public class ProductGroup
{

    [BsonRepresentation(BsonType.ObjectId)]
    public ObjectId _id { get; set; }

    public string Name { get; set; }

}

现在数据显示如下。

我尝试在ProductGroup中添加Technology（它是一个BsonDocument Collection）集合。

Answer 1

将您的技术模型更改为

[BsonElementAttribute("productgroups")]
public IList<ProductGroup> ProductGroups{ get; set; }

然后，

var productGroup = new BsonDocument().Add("_id", productGroup_id).Add("Name", name);

var technologies = database.GetCollection("technology");
var technology = technologies.FindOneById(ObjectId.Parse(technology_id));

technology["productgroups"] = new BsonArray().Add(BsonValue.Create(productGroup));

technologies.Save(technology);

Answer 2

1. 尽可能使用通用类型。因为此代码parent["ProductGroups"]是任何重构的危险位置。
2. 您的任务可以在一个查询中完成

var productGroup = new ProductGroup { Id = ObjectId.GenerateNewId(), Name = model.Name };
var collection = database.GetCollection<Technology>("Technology");
var update = Builders<Technology>.Update.AddToSet(x => x.ProductGroups, productGroup);
await collection.FindOneAndUpdateAsync(x => x.Id == model._id, update);

Answer 3

@CodingDefined我根据v2.0.1.27

更改了我的代码

请参阅下面的代码。非常感谢你的帮助。

var productGroup = new BsonDocument()
                      .Add("_id", ObjectId.GenerateNewId())
                      .Add("Name", model.Name);

BsonDocument parent = null;

var _parent = Collection.FindOneByIdAs(typeof(BsonDocument), model._id);

if (_parent != null)
{

   parent = _parent.ToBsonDocument();

   parent["ProductGroups"] = new BsonArray().Add(BsonValue.Create(productGroup));

   Collection.Save(parent);

}

请确保新的儿童记录未清除现有记录

parent["ProductGroups"] = parent["ProductGroups"].AsBsonArray.Add(productGroup);