How to tell XmlSerializer to serialize properties with [DefautValue(…)] always?

Question

I am using DefaultValue attribute for the proper PropertyGrid behavior (it shows values different from default in bold). Now if I want to serialize

Answer 1

As long as you don't need attributes in your Xml, if you use the DataContractSerializer instead you will get the behavior you desire.

[DataContract]
public class Test
{
    [DataMember]
    [DefaultValue(false)]
    public bool AllowNegative { get; set; }
}

void Main()
{
    var sb2 = new StringBuilder();
    var dcs = new DataContractSerializer(typeof(Test));

    using(var writer = XmlWriter.Create(sb2))
    {
        dcs.WriteObject(writer, new Test());
    }

    Console.WriteLine(sb2.ToString());  
}

produces (minus namespaces etc)

    false