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); } }
XML LINQ
Using the OfType Operator to Return Just the Comments
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("This is a new author."), new XProcessingInstruction("AuthorHandler", "new"), 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")))); foreach (XNode node in firstParticipant.Nodes().OfType<XComment>()) { Console.WriteLine(node); } } }
Using the OfType Operator to Return Just the Elements
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", "A"), new XElement("LastName", "B")), new XElement("Book", new XAttribute("type", "Author"), new XElement("FirstName", "C"), new XElement("LastName", "D")))); foreach (XNode node in firstParticipant.Nodes().OfType<XElement>()) { Console.WriteLine(node); } } }
Traversing Forward from the Current Node Using the NodesAfterSelf Method
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", new XComment("Begin Of List"), 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")), new XComment("End Of List"))); foreach (XNode node in firstParticipant.NodesAfterSelf()) { Console.WriteLine(node); } } }
Traversing Backward from an XElement Object via the PreviousNode Property
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 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(firstParticipant.NextNode.PreviousNode); } }
Calling the Only Nodes Prototype
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<XElement> elements = xDocument.Element("Books").Elements("Book"); foreach (XElement element in elements) { Console.WriteLine("Source element: {0} : value = {1}", element.Name, element.Value); } foreach (XNode node in elements.Nodes()) { Console.WriteLine("Child node: {0}", node); } } }
Calling the Only InDocumentOrder Prototype
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<XNode> nodes = xDocument.Element("Books").Elements("Book").Nodes().Reverse(); foreach (XNode node in nodes) { Console.WriteLine("Source node: {0}", node); } foreach (XNode node in nodes.InDocumentOrder()) { Console.WriteLine("Ordered node: {0}", node); } } }