用linq to xml创建xml实例code

 public static string CreatePayStateMachineXML()
        {
            XDocument root = new XDocument(new XElement("PayStateMachine"));
            
            //State "待付款"
            XElement state1 = new XElement("RefundState",
                    new XAttribute("Name","待付款"),
                    new XAttribute("State","1"),
                    new XElement("NextState", new XText("7")));
            root.Element("PayStateMachine").Add(state1);
            
            //State "支付处理中"
            XElement state7 = new XElement("PayState", new XAttribute("Name", "支付处理中"), new XAttribute("State", "7"),
                    new XElement("NextState", new XText("5")),
                    new XElement("NextState", new XText("2")));
            root.Element("PayStateMachine").Add(state7);

            //State "已付款"
            XElement state2 = new XElement("PayState", new XAttribute("Name", "已付款"), new XAttribute("State", "2"),
                    new XElement("NextState", new XText("3")));
            root.Element("PayStateMachine").Add(state2);

            //State "待退款"
            XElement state3 = new XElement("PayState", new XAttribute("Name", "待退款"), new XAttribute("State", "3"),
                    new XElement("NextState", new XText("6")));
            root.Element("PayStateMachine").Add(state3);

            //State "已退款"
            XElement state6 = new XElement("PayState", new XAttribute("Name", "已退款"), new XAttribute("State", "6"));
            root.Element("PayStateMachine").Add(state6);

            //State "支付失败"
            XElement state5 = new XElement("PayState", new XAttribute("Name", "支付失败中"), new XAttribute("State", "5"));
            root.Element("PayStateMachine").Add(state5);

            return root.ToString();
        }