Question

I am trying to serialize/deserialize the following XML code structure:

<Person>
    <Name/>
    <Age/>
    <Address>
        <BuildingNumber/>
        <Street/>
        <Town/>
        <PostCode/>
    </Address>
</Person>

using the classes

public class Person {
    public string Name { get; set; }
    public int Age { get; set; }
    public Address Address { get; set; }
}

public class Address {
    public string BuildingNumber { get; set; }
    public string Street { get; set; }
    public string Town { get; set; }
    public string PostCode { get; set; }
}

I am implemeting IXmlSerializable on both classes (it’s over-engineered for this specific example, I know, but it is required for a project I am working on which is rather more complicated!), for which serialisation works fine, but deserialisation does not.

The problem arises in the Person.ReadXml() method, which I have written as:

public void ReadXml(XmlReader reader) {
    reader.ReadStartElement();
    if (!reader.IsEmptyElement) {
        Name = reader.ReadElementContentAsString("Name", string.Empty);
        Age = reader.ReadElementContentAsInt("Age", string.Empty);
        Address = (Address)reader.ReadElementContentAs(typeof(Address), null, "Address", string.Empty);
        // Also failed: Address = (Address)reader.ReadElementContentAsObject("Address", string.Empty);
    }
    reader.ReadEndElement();
}

The final line where Address is being initialised is throwing an exception:

ReadElementContentAs() methods cannot be called on an element that has child elements. (XmlException)

Basically, how would I handle elements with child elements using IXmlSerializable?

Answer 1

I think you can simply use XmlSerializer here:

XmlSerializer serializer = new XmlSerializer(typeof(Person));
Person person = (Person)serializer.Deserialize(reader);

Serialization is also very simple:

serializer.Serialize(stream, person);

If you will need to customize xml (not your current case), then just use xml serialization attributes.