/// <summary>
    /// 创建一个xml文件
    /// </summary>
    /// <param name="fileName">文件名字</param>
    private void createXmlDoc(string fileName)
    {
      string  row=  System.Environment.NewLine;  
        XmlDocument xmlDoc = new XmlDocument();
        XmlDeclaration xde  ;//表示 XML 声明节点：<?xml version='1.0'...?>
        xde = xmlDoc.CreateXmlDeclaration("1.0", "ISO-8859-1", null);//verson:1.0 encoding:utf-8  standalone:yes(表示独立的，不依赖别的文件)
        xmlDoc.AppendChild(xde);
        XmlElement root = xmlDoc.CreateElement("BOOKS");
        root.SetAttribute("name", "根级元素");
        xmlDoc.AppendChild(root);

        XmlElement node1 = xmlDoc.CreateElement("BOOK");
        root.AppendChild(node1);

        XmlElement node11 = xmlDoc.CreateElement("AUTHOR");
        node11.InnerText = "XMROOM";
        node1.AppendChild(node11);

        XmlElement node12 = xmlDoc.CreateElement("NAME");
        node12.InnerText = "编程你最爱";
        node1.AppendChild(node12);

        XmlElement node13 = xmlDoc.CreateElement("TIME");
        node13.InnerText = "2013-11-20";
        node1.AppendChild(node13);

        XmlElement node14 = xmlDoc.CreateElement("COPYRIGHT");
        node14.InnerText = "XMROOM";
        node1.AppendChild(node14);

        string path = Server.MapPath("Xml\\") + fileName + ".xml";

        if (File.Exists(path))
        {
            File.Delete(path);
            
        }
        xmlDoc.Save(path);
    }