Question

The setup:

class Item {     private int _value;      public Item()     {         _value = 0;     }      public int Value { get { return _value; } set { _value = value; } } }  class ItemCollection : Collection<Item> {     private string _name;      public ItemCollection()     {         _name = string.Empty;     }      public string Name { get {return _name;} set {_name = value;} } } 

Now, trying to serialize using the following code fragment:

ItemCollection items = new ItemCollection();  ...  XmlSerializer serializer = new XmlSerializer(typeof(ItemCollection)); using (FileStream f = File.Create(fileName))     serializer.Serialize(f, items); 

Upon looking at the resulting XML I see that the ItemCollection.Name value is not there!

I think what may be happening is that the serializer sees the ItemCollection type as a simple Collection thus ignoring any other added properties…

Is there anyone having encountered such a problem and found a solution?

Regards,

Stécy

Answer 1

This behavior is ‘By Design’. When deriving from a collection class the Xml Seralizier will only serialize the collection elements. To work around this you should create a class that encapsulates the collection and the name and have that serialized.

class Wrapper {     private Collection<Item> _items;     private string _name;      public Collection<Item> Items { get {return _items; } set { _items = value; } }     public string Name { get { return _name; } set { _name = value; } } } 

A detailed discussion is available here: http://blogs.vertigo.com/personal/chris/Blog/archive/2008/02/01/xml-serializing-a-derived-collection.aspx