继承类型的CSV序列化

Question

I am attempting to serialise some records into CSV using the ServiceStack.Text library.

I am using inheritance, specifically abstract classes and the properties on the child types are not being output. Yes I know this is a bad idea but as I have no need to deserialise the types and I'm not making a public API. Regardless, this scenario seems to be supported by the docs.

For this example:

public abstract class ResultBase
{
    public int MinuteOffset { get; set; }
    public double SegmentDuration { get; set; }
}

public class EventIndex : IndexBase
{
    public int EventsTotal { get; set; }
    public int EventsTotalThresholded { get; set; } 
}

And the code to serialise:

var destination = new FileInfo("C:\\somefile.txt")
using (var stream =  destination.CreateText())
{
    JsvStringSerializer s = new JsvStringSerializer();
    var o = s.SerializeToString(results);
     stream.Write(o);

    CsvSerializer.SerializeToWriter(results, stream);
}

The CSV serialiser outputs this (not what I want):

MinuteOffset,SegmentDuration
0,0

But, the JSV serialiser seems to behave as expected:

[{__type:"AnalysisBase.EventIndex, AnalysisBase",EventsTotal:0,EventsTotalThresholded:0,MinuteOffset:0,SegmentDuration:0}]

Why are there differences in the fields output, is there anyway I can get the CSV serialiser to output all child properties?

Answer 1

The CsvSerializer.SerializeToWriter is a generic method which is not operating on the runtime type of the object. If you are calling for serialization through a base type of the current instance then the serializer will not now any other properties then the base one's.

public static void SerializeToWriter<T>(T value, TextWriter writer)
{
    if (value == null) return;
    if (typeof(T) == typeof(string))
    {
        writer.Write(value);
        return;
    }
    CsvSerializer<T>.WriteObject(writer, value);
}