static void Main(string[] args)
  {
   //使用XmlDocument創(chuàng)建xml
   XmlDocument xmldoc = new XmlDocument();
   XmlDeclaration xmldec = xmldoc.CreateXmlDeclaration("1.0", "utf-8", "yes");
   xmldoc.AppendChild(xmldec);

   //添加根節(jié)點(diǎn)
   XmlElement rootElement = xmldoc.CreateElement("school");
   xmldoc.AppendChild(rootElement);

   //添加根節(jié)點(diǎn)下的子節(jié)點(diǎn)元素
   XmlElement classElement = xmldoc.CreateElement("class");
   rootElement.AppendChild(classElement);
   XmlAttribute atrrClass = xmldoc.CreateAttribute("No");
   atrrClass.Value = "1";
   classElement.Attributes.Append(atrrClass);

   //添加子節(jié)點(diǎn)下的元素
   XmlElement stuElement = xmldoc.CreateElement("student");
   classElement.AppendChild(stuElement);
   XmlAttribute attrStu = xmldoc.CreateAttribute("sid");
   attrStu.Value = "20180101";
   stuElement.Attributes.Append(attrStu);

   //保存文件
   xmldoc.Save(@"d:\zzz\TestA.xml");
   Console.WriteLine("創(chuàng)建xml文件ok！");
   Console.ReadKey();

  }

static void Main(string[] args)
  {
   //使用XDocument創(chuàng)建xml
   System.Xml.Linq.XDocument xdoc = new XDocument();
   XDeclaration xdec = new XDeclaration("1.0", "utf-8", "yes");
   xdoc.Declaration = xdec;

   //添加根節(jié)點(diǎn)
   XElement rootEle = new XElement("school");
   xdoc.Add(rootEle);

   //給根節(jié)點(diǎn)添加子節(jié)點(diǎn)
   XElement classEle = new XElement("class");
   XAttribute attrClass = new XAttribute("No", 1);
   classEle.Add(attrClass);
   rootEle.Add(classEle);

   //添加子節(jié)點(diǎn)下的元素
   XElement stuEle = new XElement("student");
   XAttribute atrStu = new XAttribute("sid", "20180101");
   stuEle.Add(atrStu);
   classEle.Add(stuEle);

   //保存文件
   xdoc.Save("d:\\zzz\\TestB.xml");
   Console.WriteLine("創(chuàng)建xml文件ok");
   Console.ReadKey();
  }