Serialising / Deserialising objects to Xml in .Net

Serialising / Deserialising objects to Xml: from my StackOverFlow

private static readonly Dictionary<Type, XmlSerializer> serialisers = new Dictionary<Type, XmlSerializer>();

/// <summary>Serialises an object of type T in to an xml string</summary>
/// <typeparam name="T">Any class type</typeparam>
/// <param name="objectToSerialise">Object to serialise</param>
/// <returns>A string that represents Xml, empty oterwise</returns>
public static string XmlSerialise<T>(this T objectToSerialise) where T : class, new()
{
  XmlSerializer serialiser;

  var type = typeof(T);
  if (!serialisers.ContainsKey(type))
  {
    serialiser = new XmlSerializer(type);
    serialisers.Add(type, serialiser);
  }
  else
  {
    serialiser = serialisers[type];
  }

  string xml;
  using (var writer = new StringWriter())
  {
    serialiser.Serialize(writer, objectToSerialise);
    xml = writer.ToString();
  }

  return xml;
}

/// <summary>Deserialises an xml string in to an object of Type T</summary>
/// <typeparam name="T">Any class type</typeparam>
/// <param name="xml">Xml as string to deserialise from</param>
/// <returns>A new object of type T is successful, null if failed</returns>
public static T XmlDeserialise<T>(this string xml) where T : class, new()
{
  XmlSerializer serialiser;

  var type = typeof(T);
  if (!serialisers.ContainsKey(type))
  {
    serialiser = new XmlSerializer(type);
    serialisers.Add(type, serialiser);
  }
  else
  {
    serialiser = serialisers[type];
  }

  T newObject;

  using (var reader = new StringReader(xml))
  {
    try { newObject = (T)serialiser.Deserialize(reader); }
    catch { return null; } // Could not be deserialized to this type.
  }

  return newObject;
}

When building the serialisation I had a help from an online example – but cannot remeber where it is…