Csharp/C Sharp by API/System.Xml.Linq/XElement

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new XElement

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XDocument xDocument = new XDocument(
        new XElement("Books",
          new XElement("Book",
           new XAttribute("type", "Author"),
          new XComment("This is a new author."),
           new XElement("FirstName", "A"),
          new XElement("LastName", "B")),
          new XElement("Book",
           new XAttribute("type", "Author"),
          new XElement("FirstName", "C"),
          new XElement("LastName", "D"))));
       IEnumerable<XAttribute> attributes = xDocument.Element("Books").Elements("Book").Attributes();
       foreach (XAttribute attribute in attributes) {
           Console.WriteLine("Source attribute: {0} : value = {1}", attribute.Name, attribute.Value);
       }
       attributes.Remove();
       Console.WriteLine(xDocument);
   }

} 


 </source>


XElement.AddFirst

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       xml.AddFirst(new XElement("person",
                       new XElement("id", 5),
                       new XElement("firstname", "Tom"),
                       new XElement("lastname", "Cruise"),
                       new XElement("idrole", 1)));
       Console.WriteLine(xml);
   }

} 


 </source>


XElement.Ancestors()

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       var record = xml.Descendants("firstname").First();
       foreach (var tag in record.Ancestors())
           Console.WriteLine(tag.Name);
   }

} 


 </source>


XElement.AncestorsAndSelf()

<source lang="csharp">

using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
      new XDeclaration("1.0", "UTF-8", "yes"),
      new XDocumentType("Books", null, "Books.dtd", null),
      new XProcessingInstruction("Book", "out-of-print"),
      new XElement("Books", firstParticipant =
        new XElement("Book",
      new XComment("a new author."),
        new XProcessingInstruction("AuthorHandler", "new"),
        new XAttribute("type", "Author"),
        new XElement("FirstName",
      new XText("A"),
      new XElement("NickName", "J")),
     new XElement("LastName", "R")),
     new XElement("Book",
     new XAttribute("type", "Author"),
     new XElement("FirstName", "E"),
     new XElement("LastName", "B"))));
       foreach (XElement element in firstParticipant.
       Element("FirstName").Element("NickName").AncestorsAndSelf()) {
           Console.WriteLine(element.Name);
       }
   }

} 


 </source>


XElement.AncestorsAndSelf(String tagName)

<source lang="csharp">

using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XDocument xDocument = new XDocument(
        new XElement("Books",
          new XElement("Book",
           new XAttribute("type", "Author"),
           new XElement("FirstName", "J"),
          new XElement("LastName", "R")),
          new XElement("Book",
           new XAttribute("type", "Author"),
          new XElement("FirstName", "E"),
          new XElement("LastName", "B"))));
       IEnumerable<XElement> elements =
        xDocument.Element("Books").Descendants("FirstName");
       foreach (XElement element in elements) {
           Console.WriteLine("Source element: {0} : value = {1}",element.Name, element.Value);
       }
       foreach (XElement element in elements.AncestorsAndSelf("Book")) {
           Console.WriteLine("Ancestor element: {0}", element.Name);
       }
   }

} 


 </source>


XElement.Attribute

<source lang="csharp">

using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R"))));
       Console.WriteLine(firstParticipant.Attribute("type").Value);
   }

} 


 </source>


XElement.Changed

<source lang="csharp">

using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R")),
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "E"),
             new XElement("LastName", "B"))));
       Console.WriteLine("{0}{1}", xDocument, System.Environment.NewLine);
       firstParticipant.Changing += new EventHandler<XObjectChangeEventArgs>(
         (object sender, XObjectChangeEventArgs cea) =>
           Console.WriteLine("Type of object changing: {0}, Type of change: {1}",
             sender.GetType().Name, cea.ObjectChange));
       firstParticipant.Changed += (object sender, XObjectChangeEventArgs cea) =>
         Console.WriteLine("Type of object changed: {0}, Type of change: {1}",
           sender.GetType().Name, cea.ObjectChange);
       xDocument.Changed += (object sender, XObjectChangeEventArgs cea) =>
         Console.WriteLine("Doc: Type of object changed: {0}, Type of change: {1}{2}",
           sender.GetType().Name, cea.ObjectChange, System.Environment.NewLine);

       firstParticipant.Element("FirstName").Value = "Seph";
       Console.WriteLine("{0}{1}", xDocument, System.Environment.NewLine);
   }

} 


 </source>


XElement.Changing

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R")),
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "E"),
             new XElement("LastName", "B"))));
       Console.WriteLine(xDocument);
       firstParticipant.Changing += new EventHandler<XObjectChangeEventArgs>(MyChangingEventHandler);
       firstParticipant.Changed += new EventHandler<XObjectChangeEventArgs>(MyChangedEventHandler);
       xDocument.Changed += new EventHandler<XObjectChangeEventArgs>(DocumentChangedHandler);
   }
   public static void MyChangingEventHandler(object sender, XObjectChangeEventArgs cea)
   {
     Console.WriteLine("Type of object changing: {0}, Type of change: {1}",
       sender.GetType().Name, cea.ObjectChange);
   }

   public static void MyChangedEventHandler(object sender, XObjectChangeEventArgs cea)
   {
     Console.WriteLine("Type of object changed: {0}, Type of change: {1}",
       sender.GetType().Name, cea.ObjectChange);
   }

   public static void DocumentChangedHandler(object sender, XObjectChangeEventArgs cea)
   {
     Console.WriteLine("Doc: Type of object changed: {0}, Type of change: {1}{2}",
       sender.GetType().Name, cea.ObjectChange, System.Environment.NewLine);
   }

} 


 </source>


XElement.Descendants

<source lang="csharp">

using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       var query = from p in xml.Descendants("person")
                   join s in xml.Descendants("id")
                   on (int)p.Element("id") equals (int)s.Attribute("id")
                   select new {
                       FirstName = p.Element("firstname").Value,
                       LastName = p.Element("lastname").Value,
                       Amount = s.Attribute("salaryyear").Value
                   };
       foreach (var record in query) {
           Console.WriteLine("Employee: {0} {1}, Salary {2}", record.FirstName,
                                                           record.LastName,
                                                           record.Amount);
       }
   }

} 


 </source>


XElement.Descendants("firstname").First()

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       XElement firstName = xml.Descendants("firstname").First();
       Console.WriteLine("Is FirstName tag empty? {0}", firstName.IsEmpty ? "Yes" : "No");
       XElement idEmployee = xml.Descendants("idperson").First();
       Console.WriteLine("Is idperson tag empty? {0}", idEmployee.IsEmpty ? "Yes" : "No");
   }

} 


 </source>


XElement.Elements

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XDocument xDocument = new XDocument(
        new XElement("Books",
          new XElement("Book",
           new XAttribute("type", "Author"),
           new XElement("FirstName", "A"),
          new XElement("LastName", "B")),
          new XElement("Book",
           new XAttribute("type", "Author"),
          new XElement("FirstName", "C"),
          new XElement("LastName", "D"))));
       IEnumerable<XElement> elements = xDocument.Element("Books").Elements("Book");
       foreach (XElement element in elements) {
           Console.WriteLine("Source element: {0} : value = {1}", element.Name, element.Value);
       }
       foreach (XAttribute attribute in elements.Attributes()) {
           Console.WriteLine("Attribute: {0} : value = {1}",
            attribute.Name, attribute.Value);
       }
   }

} 


 </source>


XElement.First

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       XElement firstName = xml.Descendants("firstname").First();
       Console.WriteLine(firstName.Parent);
   }

} 


 </source>


XElement.FirstAttribute

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XAttribute("experience", "first-time"),
             new XAttribute("language", "English"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R"))));
       Console.WriteLine(firstParticipant.FirstAttribute.NextAttribute);
   }

} 


 </source>


XElement.GetSchemaInfo()

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Schema; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XDocument xDocument = new XDocument(
         new XElement("Books",
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "A"),
             new XElement("MiddleName", "Carson"),
             new XElement("LastName", "B")),
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "C"),
             new XElement("LastName", "D"))));
       Console.WriteLine(xDocument);
       XmlSchemaSet schemaSet = new XmlSchemaSet();
       schemaSet.Add(null, "bookparticipants.xsd");
       xDocument.Validate(schemaSet, (o, vea) => {
              Console.WriteLine(o.GetType().Name);
              Console.WriteLine(vea.Message);
          },true);
       foreach (XElement element in xDocument.Descendants()) {
           Console.WriteLine("Element {0} is {1}", element.Name,
             element.GetSchemaInfo().Validity);
           XmlSchemaElement se = element.GetSchemaInfo().SchemaElement;
           if (se != null) {
               Console.WriteLine(
                 "Schema element {0} must have MinOccurs = {1} and MaxOccurs = {2}{3}",
                 se.Name, se.MinOccurs, se.MaxOccurs, System.Environment.NewLine);
           } else {
               Console.WriteLine();
           }
       }
   }

} 


 </source>


XElement.HasAttributes

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       XElement firstName = xml.Descendants("firstname").First();
       Console.WriteLine("FirstName tag has attributes: {0}", firstName.HasAttributes);
       Console.WriteLine("FirstName tag has child elements: {0}", firstName.HasElements);
       Console.WriteLine("FirstName tag"s parent has attributes: {0}", firstName.Parent.HasAttributes);
       Console.WriteLine("FirstName tag"s parent has child elements: {0}", firstName.Parent.HasElements);
   }

} 


 </source>


XElement.HasElements

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       XElement firstName = xml.Descendants("firstname").First();
       Console.WriteLine("FirstName tag has attributes: {0}", firstName.HasAttributes);
       Console.WriteLine("FirstName tag has child elements: {0}", firstName.HasElements);
       Console.WriteLine("FirstName tag"s parent has attributes: {0}", firstName.Parent.HasAttributes);
       Console.WriteLine("FirstName tag"s parent has child elements: {0}", firstName.Parent.HasElements);
   }

} 


 </source>


XElement.Load(String fileName)

<source lang="csharp">

using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Hello_XLINQ.xml");
       XNamespace w = "http://schemas.microsoft.ru/office/word/2003/wordml";
       XElement defaultFonts = xml.Descendants(w + "defaultFonts").First();
       Console.WriteLine("Default Fonts: {0}", (string)defaultFonts.Attribute(w + "ascii"));
   }

} 


 </source>


XElement.Nodes()

<source lang="csharp">

using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       IEnumerable<XComment> record = xml.Nodes().OfType<XComment>();
       foreach (XComment comment in record)
           Console.WriteLine(comment);
   }

} 


 </source>


XElement.Parent

<source lang="csharp"> using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       XElement firstName = xml.Descendants("firstname").First();
       Console.WriteLine(firstName.Parent);
   }

} 


 </source>


XElement.Parse(String xml value)

<source lang="csharp">

using System; using System.Linq; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement books = XElement.Parse(
         @"<books>
       <book>
         <title>P</title>
         <author>J</author>
       </book>
       <book>
         <title>W</title>
         <author>B</author>
       </book>
       <book>
         <title>C</title>
         <author>A</author>
       </book>
   </books>");
       var titles =
        from book in books.Elements("book")
        where (string)book.Element("author") == "J"
        select book.Element("title");
       foreach (var title in titles)
           Console.WriteLine(title.Value);
   }

} 


 </source>


XElement.Remove

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "A"),
             new XElement("LastName", "B")),
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "C"),
             new XElement("LastName", "D"))));
       Console.WriteLine(xDocument);
       firstParticipant.Remove();
       Console.WriteLine(xDocument);
   }

} 


 </source>


XElement.RemoveAll

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XDocument xDocument = new XDocument(
         new XElement("Books",
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R")),
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "E"),
             new XElement("LastName", "B"))));
       Console.WriteLine(xDocument);
       xDocument.Element("Books").RemoveAll();
       Console.WriteLine(xDocument);
   }

} 


 </source>


XElement.Save(String fileName)

<source lang="csharp">

using System; using System.Collections; using System.Collections.Generic; using System.Linq; using System.Text; using System.Data.Linq; using System.Reflection; using System.Xml.Linq; class Program { 

   static void Main(string[] args) {
       XElement xml = XElement.Load("Employee.xml");
       XElement html = new XElement("HTML",
                               new XElement("BODY",
                                   new XElement("TABLE",
                                       new XElement("TH", "ID"),
                                       new XElement("TH", "Full Name"),
                                       new XElement("TH", "Role"),
                                           from p in xml.Descendants("person")
                                           join r in xml.Descendants("role") on (int)p.Element("idrole") equals (int)r.Element("id")
                                           select new XElement("TR",
                                                           new XElement("TD", p.Element("id").Value),
                                                           new XElement("TD", p.Element("firstname").Value + " " + p.Element("lastname").Value),
                                                           new XElement("TD", r.Element("roledescription").Value)))));
       html.Save(@"C:\People.html");
   }

} 


 </source>


XElement.SetAttributeValue

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XAttribute("experience", "first-time"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R"))));
       Console.WriteLine(xDocument);
       firstParticipant.SetAttributeValue("type", "beginner");
       firstParticipant.SetAttributeValue("language", "English");
       firstParticipant.SetAttributeValue("experience", null);
       Console.WriteLine(xDocument);
   }

} 


 </source>


XElement.SetElementValue

<source lang="csharp"> using System; using System.Linq; using System.Collections; using System.Collections.Generic; using System.Xml; using System.Xml.Linq; public class MainClass { 

   public static void Main() {
       XElement firstParticipant;
       XDocument xDocument = new XDocument(
         new XElement("Books", firstParticipant =
           new XElement("Book",
             new XAttribute("type", "Author"),
             new XElement("FirstName", "J"),
             new XElement("LastName", "R"))));
       Console.WriteLine(xDocument);
       firstParticipant.SetElementValue("FirstName", "Joseph");
       firstParticipant.SetElementValue("MiddleInitial", "C");
       firstParticipant.SetElementValue("LastName", null);
       Console.WriteLine(xDocument);
   }

} 


 </source>
Источник — «http://nfex.ru/index.php?title=Csharp/C_Sharp_by_API/System.Xml.Linq/XElement&oldid=4514»