How to exclude null properties when using XmlSerializer

Question

I\'m serializing a class like this

public MyClass
{
    public int? a { get; set; }
    public int? b { get; set; }
    public int? c { get; set; }
}


        

Answer 1

I suppose you could create an XmlWriter that filters out all elements with an xsi:nil attribute, and passes all other calls to the underlying true writer.

Answer 2

Better late than never...

I found a way (maybe only available with the latest framework I don't know) to do this. I was using DataMember attribute for a WCF webservice contract and I marked my object like this:

[DataMember(EmitDefaultValue = false)]
public decimal? RentPrice { get; set; }

Answer 3

1) Extension

 public static string Serialize<T>(this T value) {
        if (value == null) {
            return string.Empty;
        }
        try {
            var xmlserializer = new XmlSerializer(typeof(T));
            var stringWriter = new Utf8StringWriter();
            using (var writer = XmlWriter.Create(stringWriter)) {
                xmlserializer.Serialize(writer, value);
                return stringWriter.ToString();
            }
        } catch (Exception ex) {
            throw new Exception("An error occurred", ex);
        }
    }

1a) Utf8StringWriter

public class Utf8StringWriter : StringWriter {
    public override Encoding Encoding { get { return Encoding.UTF8; } }
}

2) Create XElement

XElement xml = XElement.Parse(objectToSerialization.Serialize());

3) Remove Nil's

xml.Descendants().Where(x => x.Value.IsNullOrEmpty() && x.Attributes().Where(y => y.Name.LocalName == "nil" && y.Value == "true").Count() > 0).Remove();

4) Save to file

xml.Save(xmlFilePath);