将 mongodb 文档序列化为域对象

Question

我正在尝试将 mondodb 文档读入我的域 class (Company)，但其中一个属性出现错误。错误消息如下：

"Expected a nested document representing the serialized form of a OrgNumber value, but found a value of type String instead"

对象看起来像这样：

public class OrgNumber
{
    public string Value { get; private set; }
    ...

    private OrgNumber() { }

    public OrgNumber(string value) {
            Value = value;
    }
}

public class Company
{
    public string Name { get; private set; }
    public OrgNumber OrgNumber { get; private set; }
    ...

    private Company() { }

    public Company(string name, OrgNumber orgNumber)
    {
            Name = name;
            OrgNumber = orgNumber;
    }
}

mongodb 文档如下所示：

{
"name": "Company name",
"orgNumber": "1234-5678",
}

我正在阅读文档并将其直接映射到我的域模型中：

var collection = _mongoDb.GetCollection<Company>("Companies");
var result = await collection.Find(c => c.CompanyId == companyId).SingleOrDefaultAsync();

如何正确地将 OrgNumber 的字符串表示形式转换为正确的类型 OrgNumber？

Answer 1

您可以创建自己的继承自 SerializerBase<T>

的序列化程序

public class OrgNumberSerializer : SerializerBase<OrgNumber>
{
    public override OrgNumber Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
    {
        var serializer = BsonSerializer.LookupSerializer(typeof(string));
        var data = serializer.Deserialize(context, args);
        return new OrgNumber(data.ToString());
    }

    public override void Serialize(BsonSerializationContext context, BsonSerializationArgs args, OrgNumber value)
    {
        var serializer = BsonSerializer.LookupSerializer(typeof(string));
        serializer.Serialize(context, value.Value);
    }
}

然后需要使用以下行进行全局注册：

BsonSerializer.RegisterSerializer(typeof(OrgNumber), new OrgNumberSerializer());

您可以找到更多详情here

将 mongodb 文档序列化为域对象

Serialize mongodb document to domain object

c#

mongodb

mongodb-csharp-2.0

mongodb-.net-driver