public void TestLinq2Xml()
{
const string Text = @"<Metadata xmlns:xsd=""http://www.w3.org/2001/XMLSchema"" xmlns:xsi=""http://www.w3.org/2001/XMLSchema-instance"">
<Meta xsi:type=""Readonly"" />
<Meta xsi:type=""Garbage"" />
</Metadata>";
// Get the "names" of all implementors of MetadataBase
var types = AppDomain.CurrentDomain.GetAssemblies().ToList()
.SelectMany(s => s.GetTypes())
.Where(p => typeof(MetadataBase).IsAssignableFrom(p) && !p.IsAbstract && !p.IsInterface)
.Where(t => t.GetCustomAttributes(typeof(XmlTypeAttribute), false).Any())
.Select(t => t.GetCustomAttributes(typeof(XmlTypeAttribute), false)
.Cast<XmlTypeAttribute>().First().TypeName);
// Create a parser
var parser = new XmlSerializer(typeof(MetadataBase));
// Create metadatacontainer to fill
var metas = new MetadataContainer();
// Fill it with matching from from the XML
metas.AddRange((from t in XDocument.Parse(Text).Descendants("Meta")
where types.Contains(t.Attribute(XName.Get("type", "http://www.w3.org/2001/XMLSchema-instance")).Value)
select (MetadataBase)parser.Deserialize(t.CreateReader())).ToList());
// Should be one guy present
Assert.AreEqual(metas.Count, 1);
}