将 Mongo 位置坐标的 BSON 数组反序列化为自定义 C# class

Question

我有一份文件存储在 Mongo 中，格式如下：

"address" : {
    "building" : "469",
    "coord" : [ 
        -73.961704, 
        40.662942
    ],
    "street" : "Flatbush Avenue",
    "zipcode" : "11225"
}

我正在使用官方 C# Mongo 驱动程序与 MongoDB 实例进行通信。我定义了如下POCOclasses来对应文档：

public class Coordinate
{
    public float Lat { get; set; }
    public float Long { get; set; }
}

public class Address
{
    [BsonElement("street")]
    public string Street { get; set; }
    [BsonElement("zipcode")]
    public string ZipCode { get; set; }
    [BsonElement("building")]
    public string Building { get; set; }
    [BsonElement("coord")]
    public Coordinate Coord { get; set; }
}

但我不确定在序列化属性方面必须做什么，以便将坐标 BSON 数组值反序列化为我创建的坐标 class。

有什么想法吗？

Answer 1

您需要创建自定义 serializer:

public class MyCustomArraySerializer : SerializerBase<Coordinate>
{
    public override Coordinate Deserialize(BsonDeserializationContext context, BsonDeserializationArgs args)
    {
        context.Reader.ReadStartArray();
        var lat=context.Reader.ReadDouble();
        var lon = context.Reader.ReadDouble();
        context.Reader.ReadEndArray();

        return new Coordinate() { Long = (float)lon, Lat = (float)lat };
    }
    public override void Serialize(BsonSerializationContext context, BsonSerializationArgs args, Coordinate value)
    {
        context.Writer.WriteStartArray();
        context.Writer.WriteDouble(value.Lat);
        context.Writer.WriteDouble(value.Long);
        context.Writer.WriteEndArray();
    }
}

然后在Coord上添加这个属性属性:

public class Address
{
    //...
    //Add this attribute
    [BsonSerializer(typeof(MyCustomArraySerializer))]
    public Coordinate Coord { get; set; }
}

将 Mongo 位置坐标的 BSON 数组反序列化为自定义 C# class

Deserialize Mongo BSON array of location coordinates to custom C# class

c#

geolocation

mongodb

bson