无法将类型为"MongoDB.Bson.Serialization.Serializers.DateTimeSerializer"的对象转换为类型为"MongoDB.Bson.Serialization.IBsonSerializer"的对象. [英] Unable to cast object of type 'MongoDB.Bson.Serialization.Serializers.DateTimeSerializer' to type 'MongoDB.Bson.Serialization.IBsonSerializer`

问题描述

在寻找解决方案时，我得到了此和

While searching for the solution I got this and this but the concept was not clear to me so couldn't implement it :(. This error occurs when I try to update values in the database(specifically for datetime objects). Below is the code that I'm using:-

     var update = Builders<Model>.Update
            .Set(t => t.startdate, BsonValue(objModel.startdate));
     var result = model.UpdateOne(query, update);

和BonValue函数如下:-

and BonValue function is as follows:-

   private static BsonValue BsonValue(object obj)
    {
        if (obj == null)
            return (BsonValue)obj ?? BsonNull.Value;
        else if (obj.GetType() == typeof(string))
            return new BsonString(obj.ToString());
        else if (obj.GetType() == typeof(DateTime))
            return new BsonDateTime(DateTime.SpecifyKind(DateTime.Parse(obj.ToString()), DateTimeKind.Utc));
        else if (obj.GetType() == typeof(int))
            return new BsonInt32(int.Parse(obj.ToString()));
        else
            return (BsonValue)obj;
    } 

我认为这是因为我已经开始使用mongoDB.Bson和mongoDB.Driver的升级包.当前版本是2.3.0

I think this is because I have started using upgraded packages of mongoDB.Bson and mongoDB.Driver. Current version is 2.3.0

任何帮助将不胜感激.

修改

1)在插入数据时我的工作如下:-

1) while Inserting data what i do is as follows:-

    BsonDocument objBsonDoc = new BsonDocument {
            { "startdate",DataManager.GetBsonValue( objModel.startdate) }
        }; return dbHelper.CreateDocument(Model.CollectionName, objBsonDoc);  

在objBsonDoc中，我可以看到StartDate值，但是在CreateDocument命令StartDate之后没有将其保存在数据库中.

In objBsonDoc I can see the StartDate value but after CreateDocument command StartDate doesn't get saved in DB.

2)这是我在更新值时正在做的事情:-

2) This is what I'm doing while updating values:-

    public static long Edit(Model objModel, string id)
    {
        IMongoCollection<Model> model = dbHelper.GetCollection<Model>(Model.CollectionName);

        var query = Builders<Model>.Filter.Eq(t => t.id, ObjectId.Parse(id));

        var update = Builders<Model>.Update
            .Set(t => t.startdate, objModel.startdate);

        var result = model.UpdateOne(query, update);
        return result.MatchedCount;
    }

在这里我也获得开始日期的值，并且还获得Modifyed = 1，但是当我检查数据库时它仍然显示开始状态为空.

here also i get the value for start date and also getting modifiedcount=1 but still when i check DB it shows null for start sate.

我的模型课:-

    public class Model
{
    public static string CollectionName
    {
        get { return "Collection"; }
    }

    public ObjectId id { get; set; }

    [BsonDateTimeOptions(Kind = DateTimeKind.Utc)]
    [BsonRepresentation(BsonType.DateTime)]
    public DateTime startdate { get; set; }
}

推荐答案

您不需要按照自己的方式执行自己的转换.

You shouldn't need to perform your own conversion the way you are.

尝试在模型上设置BsonRepresentation

Try setting the BsonRepresentation on your model

public class Model
{
    [BsonDateTimeOptions(Kind = DateTimeKind.Utc)]
    [BsonRepresentation(BsonType.DateTime)]
    public DateTime startDate { get; set; }
}

为了澄清起见，我可以建议您将集合变量重命名为collection，而不是像model这样混淆，所以

For the sake of clarify can i suggest you rename your collection variable to collection instead of model as this in confusing, so

IMongoCollection<Model> collection = dbHelper.GetCollection<Model>(Model.CollectionName);

Model objModel = new Model { startDate = DateTime.UtcNow };
collection.InsertOne(yourModel);

要执行更新，您无需设置为BsonValue

And to perform your update you won't need to set to BsonValue

 var query = Builders<Model>.Filter.Eq(t => t.Id, ObjectId.Parse(id));
 var update = Builders<Model>.Update.Set(t => t.startdate, objModel.startdate);
 var result = model.UpdateOne(query, update);

一个建议是将ObjectId存储为字符串，并像使用DateTime一样使用BsonRepresentation:

One suggestion, is to store your ObjectId as string and use BsonRepresentation as you have with DateTime:

[BsonRepresentation(BsonType.ObjectId)]
[BsonId]
public string Id { get; set; }

那样，您无需费劲将其解析为ObjectId，并且它的工作原理相同，因此您的过滤器将变为

That way you don't need to go out of your way to parse it to ObjectId and it works the same, so your filter becomes

var query = Builders<Model>.Filter.Eq(t => t.Id, id);

或者您可以像这样直接在更新中使用Lambda:

Or you could use Lambda directly in your update like so:

var update = Builders<Model>.Update
    .Set(t => t.Id == id, objModel.startdate);

这篇关于无法将类型为"MongoDB.Bson.Serialization.Serializers.DateTimeSerializer"的对象转换为类型为"MongoDB.Bson.Serialization.IBsonSerializer"的对象.的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！