使用mongoDB c＃驱动程序将对象序列化为字符串值（就像在其上调用ToString（））

Question

I am using MongoDB C# driver. I have a datastructure in C#

public class ResourceSpec
{
      public string TypeName
      {
          get;
          private set;
      }

      public HashSet<ResourceProperty> Properties
      {
          get;
          private set;
      }
}

public class ResourceProperty
{
     public string Val
     {
         get;
         private set;
     }
} 

I want it to be serialized into:

{TypeName: 'blabla', Properties: ['value1', 'value2', 'value3' ]}

Instead of

{TypeName: 'blabla', Properties: [{Val: 'value1'}, {Val: ' value2'}, {Val: ' value3'}] }

How can I do that?

Answer 1

You can write a custom serializer and register it with the driver. One thing to note that once you register your serializer it will be used for every ResourceSpec instance.

public class ResourceSpecSerializer : BsonBaseSerializer
{
    public override object Deserialize(BsonReader bsonReader, Type nominalType, Type actualType, IBsonSerializationOptions options)
    {
        // Deserialize logic
    }

    public override void Serialize(BsonWriter bsonWriter, Type nominalType, object value, IBsonSerializationOptions options)
    {
        // Serialize logic
    }

And register it using BsonSerializer.RegisterSerializer

BsonSerializer.RegisterSerializer(typeof(ResourceSpec), new ResourceSpecSerializer());

For implementing the custom JSON, i suggest looking into Json.NET and specificly JsonWriter

Here is an example of using JsonWriter :

StringBuilder sb = new StringBuilder();
StringWriter sw = new StringWriter(sb); 

using(JsonWriter writer = new JsonTextWriter(sw))
{
    writer.Formatting = Formatting.Indented;

    writer.WriteStartObject();
    writer.WritePropertyName("CPU");
    writer.WriteValue("Intel");
    writer.WritePropertyName("PSU");
    writer.WriteValue("500W");
    writer.WritePropertyName("Drives");
    writer.WriteStartArray();
    writer.WriteValue("DVD read/writer");
    writer.WriteComment("(broken)");
    writer.WriteValue("500 gigabyte hard drive");
    writer.WriteValue("200 gigabype hard drive");
    writer.WriteEnd();
    writer.WriteEndObject();
}

Will display:

 {
    "CPU": "Intel",
    "PSU": "500W",
    "Drives": [
         "DVD read/writer"
         /*(broken)*/,
        "500 gigabyte hard drive",
        "200 gigabype hard drive"
     ]
 }