假设你有下一节课。它包含代理工作过的系统
public class AgentHistory
{
public ObjectId Id { get; set; }
public Guid SystemId { get; set; }
public Guid CampaignId { get; set; }
public List<Agent> Agents { get; set; }
}
现在,当我得到一个新代理时,我会做下一件事:
public override AgentHistory Save(AgentHistory agent)
{
if (agent == null)
throw new ArgumentNullException("agent");
if (_repository.Exists(agent))
{
AgentHistory dbEntity = _repository.FindById(agent.SystemId, agent.CampaignId);
dbEntity.Agents.AddRange(agent.Agents);
_repository.UpdateAgentHistory(dbEntity);
}
else
{
_repository.Save(agent);
}
return agent;
}
存储库中的下一个方法:
public void UpdateAgentHistory(AgentHistory updatedEntity)
{
QueryComplete query = Query.EQ("_id", BsonValue.Create(updatedEntity.Id));
MongoCollection.Update(query, Update.Set("Agents", BsonArray.Create(updatedEntity.Agents)), UpdateFlags.None, SafeMode.True );
}
我得到下一个异常.NET 类型 Riverdale.Domain.BO.Agent 无法映射到 BsonValue。我做错了什么?更新嵌入式集合的正确方法是什么?
这是一个更简单的控制台应用程序,它会抛出(仅作为演示):
public class Agent
{
[BsonId]
public string LocalIdentifier { get; set; }
public string AgentName { get; set; }
}
public class A
{
public ObjectId Id { get; set; }
public Guid SystemId { get; set; }
public Guid CampaignId { get; set; }
public Agent[] Agents { get; set; }
}
public class AgentHistoryRepository
{
public bool Exists(A agentHistory)
{
return _mongoCollection.FindOne(BuildIdentityQuery(agentHistory)) != null;
}
public void Delete(A agentHistory)
{
_mongoCollection.Remove(BuildIdentityQuery(agentHistory));
}
public List<string> GetAgentsForASystem(Guid systemGuid)
{
QueryComplete query = Query.EQ("SystemId", systemGuid);
return _mongoCollection.Find(query).SelectMany(x => x.Agents.Select(z => z.AgentName)).Distinct().ToList();
}
public List<string> GetAgentsForACampaign(Guid systemGuid, Guid campaignGuid)
{
QueryComplete query = Query.EQ("CampaignId", campaignGuid);
if (systemGuid != Guid.Empty)
query = Query.And(new[] {query, Query.EQ("SystemId", systemGuid)});
return _mongoCollection.Find(query).SelectMany(x => x.Agents.Select(z => z.AgentName)).Distinct().ToList();
}
public AgentHistoryRepository()
{
string connectionString = "mongodb://localhost/Sample";
var mgsb = new MongoUrlBuilder(connectionString);
var MongoServer = MongoDB.Driver.MongoServer.Create(mgsb.ToMongoUrl());
var MongoDatabase = MongoServer.GetDatabase(mgsb.DatabaseName);
_mongoCollection = MongoDatabase.GetCollection<A>("AgentHistory");
}
private MongoCollection<A> _mongoCollection;
private QueryComplete BuildIdentityQuery(A agentHistory)
{
QueryComplete query = Query.And(Query.EQ("SystemId", agentHistory.SystemId),
Query.EQ("CampaignId", agentHistory.CampaignId));
return query;
}
public void Save(A entity)
{
_mongoCollection.Insert(entity, SafeMode.True);
}
public void UpdateAgents(A entity)
{
_mongoCollection.Update(BuildIdentityQuery(entity), Update.Set("Agents", entity.Agents.ToBsonDocument()));
}
}
internal class Program
{
public static void Main()
{
var objectToSave = new A {Id = ObjectId.GenerateNewId(), CampaignId=Guid.NewGuid(), SystemId =Guid.NewGuid() ,
Agents = new [] {new Agent{LocalIdentifier="agent", AgentName= "name"}}};
var repo = new AgentHistoryRepository();
repo.UpdateAgents(objectToSave);
objectToSave.Agents = new[] { new Agent { LocalIdentifier = "agent2", AgentName = "name2" } };
repo.UpdateAgents(objectToSave);
var objectToSave2 = new A
{
Id = ObjectId.GenerateNewId(),
CampaignId = Guid.NewGuid(),
SystemId = objectToSave.SystemId,
Agents = new [] { new Agent { LocalIdentifier = "agent", AgentName = "name" } }
};
repo.UpdateAgents(objectToSave2);
foreach (var agentName in repo.GetAgentsForASystem(objectToSave.SystemId))
Console.WriteLine(agentName);
}
}
最佳答案
您不必如此冗长:BsonValue.Create()
和 BsonArray.Create
不应该是必需的。
事实上,后者是导致问题的原因:BsonArray.Create
创建值类型数组。但是,您需要一个对象数组。如果您查看 BsonArray.Create
的可用重载,我猜您将调用 BsonArray.Create(IEnumerable)
,这是不可取的。
你试过简单地使用
MongoCollection.Update(query, Update.Set("Agents", updatedEntity.Agents), ...);
代替?
在 JSON 中,差异如下所示:
Array of Values: [ val, val, ... ]
Array of Objects: [ { ... }, { ... }, ... ]
例如,
简单数组:[ "mongodb", "awesomness", ... ]
对象数组:[ { userId: 2314234, comment: "Foo"}, { ... }, ... ]
关于c# - 使用 C# 更新 mongodb 中的嵌入式文档,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/8092552/