C# Object Serialization to XML file

public class XmlSerializationManager
{
 public static void SaveObjectToXmlFile(String path, Object _object, Type _type)
 {
  FileStream stream = File.Open(path, FileMode.Create, FileAccess.Write);

  XmlSerializer serializer = new XmlSerializer(_type);
  serializer.Serialize(stream, _object);

  stream.Close();
 }

 public static void SaveObjectToXmlFile(String path, Object _object, Type _type, Type[] extraTypes)
 {
  FileStream stream = File.Open(path, FileMode.Create, FileAccess.Write);

  XmlSerializer serializer = new XmlSerializer(_type, extraTypes);
  serializer.Serialize(stream, _object);

  stream.Close();
 }

 public static Object LoadObjectFromXmlFile(String path, Type _type)
 {
  if (!File.Exists(path))
  {
   return null;
  }

  FileStream stream = File.Open(path, FileMode.Open, FileAccess.Read);

  if (stream.Length == 0)
  {
   return null;
  }

  XmlSerializer serializer = new XmlSerializer(_type);
  Object _object = serializer.Deserialize(stream);

  stream.Close();

  return _object;
 }

 public static Object LoadObjectFromXmlFile(String path, Type _type, Type[] extraTypes)
 {
  if (!File.Exists(path))
  {
   return null;
  }

  FileStream stream = File.Open(path, FileMode.Open, FileAccess.Read);

  if (stream.Length == 0)
  {
   return null;
  }

  XmlSerializer serializer = new XmlSerializer(_type, extraTypes);
  Object _object = serializer.Deserialize(stream);

  stream.Close();

  return _object;
 }
}