在C#中要想将一个类序列化为XML，则使用XmlSerializer类：
XmlSerializer serializer = new XmlSerializer( typeof (PurchaseOrder));
TextWriter writer = new StreamWriter(filename);
PurchaseOrder po = new PurchaseOrder();
// Serialize the purchase order, and close the TextWriter.
serializer.Serialize(writer, po);
writer.Close();
可以参考WebService生成代理类的结构
