C#怎么把显示子节文本值叠加

Question

    public static  string  ShowXml()
    {
        xmlDoc = new XmlDocument();
        xmlDoc.Load("F:\\6.4迭代一\\Virtual Exchange\\TradeCenterUI\\MailSendOut.xml"); //加载xml文件
        XmlNode xn = xmlDoc.SelectSingleNode("bookshop");

        XmlNodeList xnl = xn.ChildNodes;

        foreach (XmlNode xnf in xnl)
        {
            XmlElement xe = (XmlElement)xnf;
            Console.WriteLine(xe.GetAttribute("genre"));//显示属性值 
            Console.WriteLine(xe.GetAttribute("ISBN"));

            XmlNodeList xnf1 = xe.ChildNodes;
            foreach (XmlNode xn2 in xnf1)
            {
                Console.WriteLine(xn2.InnerText);//显示子节点点文本  
            }

        }
        return xnl.ToString();

       　
    }

Answer 1

什么叫叠加？
string s = "";
foreach (XmlNode xnf in xnl)
{
XmlElement xe = (XmlElement)xnf;
Console.WriteLine(xe.GetAttribute("genre"));//显示属性值
Console.WriteLine(xe.GetAttribute("ISBN"));

        XmlNodeList xnf1 = xe.ChildNodes;
        foreach (XmlNode xn2 in xnf1)
        {
           s += xn2.InnerText; 
        }

    }
            这样？