/// <summary>
/// Gets the Serialization Information for serializing a Graph.
/// </summary>
/// <param name="info">Serialization Information.</param>
/// <param name="context">Streaming Context.</param>
public void GetObjectData(SerializationInfo info, StreamingContext context)
{
info.AddValue("base", BaseUri.ToSafeString());
info.AddValue("triples", Triples.ToList(), typeof(List <Triple>));
IEnumerable <KeyValuePair <String, String> > ns = from p in NamespaceMap.Prefixes
select new KeyValuePair <String, String>(p, NamespaceMap.GetNamespaceUri(p).AbsoluteUri);
info.AddValue("namespaces", ns.ToList(), typeof(List <KeyValuePair <String, String> >));
}