linq xml 查询

class Program
    ...{
        static void Main(string[] args)
        ...{
            XElement xml =
                new XElement("Persons",
                    new XElement("Person",
                        new XElement("Name", "刘备"),
                        new XElement("Age", "28")
                        ),
                    new XElement("Person",
                        new XElement("Name", "关羽"),
                        new XElement("Age", "27")
                        )
                    );
            xml.Save(@"D:\\123.xml");

            Console.ReadKey();
        }
    }

		

<?xml version="1.0" encoding="utf-8"?>
<Persons>
  <Person>
    <Name>刘备</Name>
    <Age>28</Age>
  </Person>
  <Person>
    <Name>关羽</Name>
    <Age>27</Age>
  </Person>
</Persons>

		

class Program
    ...{
        static void Main(string[] args)
        ...{
            //创建处理指令
            XProcessingInstruction instruction = new XProcessingInstruction("xml-stylesheet","href=\\"hello.css\\" type = \\"text/css\\"");
            //创建声明对象
            XDeclaration xDeclaration = new XDeclaration("1.0","GB2312","yes");
            //创建文档类型
            XDocumentType documentType = new XDocumentType("Person", null, "Person.dtd", null);
            //创建XmlCData数据
            XCData data = new XCData("<h1>神奇的刘备</h1>");
            //创建XDocument文档
            XDocument xDoc = new XDocument();
            XElement xml =
                new XElement("Persons",
                    new XElement("Person",
                        new XAttribute("Description", "此人龙凤之姿 天日之表;"),
                        new XElement("Name", data),
                        new XElement("Age", "28")
                        ),
                    new XElement("Person",
                        new XElement("Name", "关羽"),
                        new XElement("Age", "27")
                        )
                    );
            xDoc.Add(documentType);
            xDoc.Add(instruction);
            xDoc.Declaration = xDeclaration;
            xDoc.Add(xml);
            
            xDoc.Save(@"D:\\123.xml");

            Console.ReadKey();
        }
    }

		

<?xml version="1.0" encoding="gb2312" standalone="yes"?>
<!DOCTYPE Person SYSTEM "Person.dtd">
<?xml-stylesheet href="hello.css" type = "text/css"?>
<Persons>
  <Person Description="此人龙凤之姿 天日之表;">
    <Name><![CDATA[<h1>神奇的刘备</h1>]]></Name>
    <Age>28</Age>
  </Person>
  <Person>
    <Name>关羽</Name>
    <Age>27</Age>
  </Person>
</Persons>

		

static void Main(string[] args)
        ...{
            string xmlString = "<?xml version=\\"1.0\\" encoding=\\"utf-8\\"?><Persons><Person Description=\\"牛人\\"><Name>刘备</Name><Age>28</Age></Person></Persons>";
            XElement xe = XElement.Parse(xmlString,LoadOptions.SetLineInfo);
            //读取属性值
            string ArriValue = xe.Elements("Person").First().Attribute("Description").Value;
            //又或者
            //string ArriValue = xe.Element("Person").Attribute("Description").Value;
            Console.WriteLine(ArriValue);   //输出 牛人

            //读取元素  读取Name的后面的第一个兄弟元素
            XElement xe1 = xe.Element("Person").Element("Name").ElementsAfterSelf().First();
            Console.WriteLine(xe1.Value);   //输出 28
            //读取父节点
            XElement xe2 = xe1.Parent;
            Console.WriteLine(xe2.Name);

            Console.ReadKey();
        }

			

class Program
...{
    static void Main(string[] args)
    ...{
        var xDoc = new XDocument(new XElement( "root",
            new XElement("dog",
                new XText("dog said black is a beautify color"),
                new XAttribute("color", "black")),
            new XElement("cat"),
            new XElement("pig", "pig is great")));

        //xDoc输出xml的encoding是系统默认编码，对于简体中文操作系统是gb2312
        //默认是缩进格式化的xml，而无须格式化设置

        xDoc.Save(Console.Out);
        Console.WriteLine();

        var query = from item in xDoc.Element( "root").Elements()
                    select new
                    ...{
                        TypeName    = item.Name,
                        Saying      = item.Value,
                        Color       = item.Attribute("color") == null?(string)null:item.Attribute("color").Value
                    };

        foreach (var item in query)
        ...{
            Console.WriteLine("{0} 's color is {1},{0} said {2}",item.TypeName,item.Color??"Unknown",item.Saying??"nothing");
        }
        Console.Read();
    }
}

			

static void Main(string[] args)
        ...{
            string xmlString = "<?xml version=\\"1.0\\" encoding=\\"utf-8\\"?><Persons><Person Description=\\"牛人\\"><Name>刘备</Name><Age>28</Age></Person></Persons>";
            XElement xe = XElement.Parse(xmlString, LoadOptions.SetLineInfo);

            //这是添加在最后，如果想添加在最前面可以使用AddFirst,
            //添加在本节点之前AddBeforSelf，添加在本节点之后AddAfterSelf
            xe.Add(new XElement("Person",
                        new XElement("Name", "关羽"),
                        new XElement("Age", 26)
                    )
                );
            //删除所有子节点
            xe.RemoveAll();
标签：
linq