XML Serialization - Is it possible to serialize a model in this way? - serialization

Question

I have the following model:
public class ABaseObject
{
private Guid id = Guid.NewGuid();
public ABaseObject()
{
}
public Guid ID { get { return id; } }
}
public class ADerivedObject : ABaseObject
{
public ADerivedObject()
{
}
public string Name { get; set; }
}
public class AObjectCollection<T>
{
private List<T> items = new List<T>();
public AObjectCollection()
{
}
public IEnumerable<T> Items { get { return items; } }
public void Add(T item)
{
items.Add(item);
}
public void Save(string filePath)
{
FileStream writer = new FileStream(filePath, FileMode.Create);
DataContractSerializer s = new DataContractSerializer(typeof(T));
s.WriteObject(writer, this);
writer.Close();
}
public void Load(string filePath)
{
FileStream fs = new FileStream(filePath, FileMode.Open);
XmlDictionaryReader reader = XmlDictionaryReader.CreateTextReader(fs, new XmlDictionaryReaderQuotas());
DataContractSerializer ser = new DataContractSerializer(typeof(T));
// Deserialize the data and read it from the instance.
T deserializedObj = (T)ser.ReadObject(reader, true);
reader.Close();
fs.Close();
}
}
So basically I want to be able to do the following:
var der = new ADerivedObject();
der.Name = "Test";
var col = new AObjectCollection<ADerivedObject>();
col.Add(der);
col.Save("C:\MyCollection.xml");
...
var col2 = new AObjectCollection<ADerivedObject>();
col2.Load("C:\MyCollection.xml");
When serialized it should look something like:
<Collection>
<Item>
<ID></ID>
<Name></Name>
</Item>
</Collection>
I have played around with DataContracts and XmlSerializer but I can't quite seem to find a way to do it.

Answer 1

This code:
public class ABaseObject
{
public ABaseObject() { }
public Guid ID { get; set;}
}
[XmlType("Item")]
public class ADerivedObject : ABaseObject
{
public ADerivedObject() {}
public string Name { get; set; }
}
[XmlType("Collection")]
public class AObjectCollection<T>
{
private System.Xml.Serialization.XmlSerializerNamespaces ns;
private System.Xml.Serialization.XmlSerializer s;
public AObjectCollection()
{
ns= new System.Xml.Serialization.XmlSerializerNamespaces();
ns.Add( "", "");
s= new System.Xml.Serialization.XmlSerializer(this.GetType());
Items = new List<T>();
}
public List<T> Items { get; set; }
public DateTime LastSaved { get;set; }
public void Add(T item)
{
Items.Add(item);
}
public void Save(string filePath)
{
LastSaved= System.DateTime.Now;
var xmlws = new System.Xml.XmlWriterSettings { OmitXmlDeclaration = true, Indent= true };
using ( var writer = System.Xml.XmlWriter.Create(filePath, xmlws))
{
s.Serialize(writer, this, ns);
}
}
public static AObjectCollection<T2> Load<T2>(string filepath)
{
AObjectCollection<T2> obj;
try
{
var s= new System.Xml.Serialization.XmlSerializer(typeof(AObjectCollection<T2>));
using(System.IO.StreamReader reader= System.IO.File.OpenText(filepath))
{
obj= (AObjectCollection<T2>) s.Deserialize(reader);
}
}
catch
{
obj= new AObjectCollection<T2>();
}
return obj;
}
}
produces this output:
<Collection>
<Items>
<Item>
<ID>00000000-0000-0000-0000-000000000000</ID>
<Name>Test</Name>
</Item>
</Items>
<LastSaved>2010-02-04T07:32:05.812-05:00</LastSaved>
</Collection>
There are ways to tweak the XML to remove the Collection/Items layer. Search SO for other Collection / Serialization questions.