LINQ - XML
LINQ to XML offre un accès facile à toutes les fonctionnalités de LINQ telles que les opérateurs de requête standard, l'interface de programmation, etc. et bien plus à dire.
Introduction de LINQ to XML
Lors de l'utilisation de LINQ to XML, le chargement de documents XML en mémoire est facile et plus facile est l'interrogation et la modification de document. Il est également possible de sauvegarder sur disque les documents XML existants en mémoire et de les sérialiser. Il élimine le besoin pour un développeur d'apprendre le langage de requête XML qui est quelque peu complexe.
LINQ to XML a sa puissance dans l'espace de noms System.Xml.Linq. Cela a toutes les 19 classes nécessaires pour travailler avec XML. Ces classes sont les suivantes.
- XAttribute
- XCData
- XComment
- XContainer
- XDeclaration
- XDocument
- XDocumentType
- XElement
- XName
- XNamespace
- XNode
- XNodeDocumentOrderComparer
- XNodeEqualityComparer
- XObject
- XObjectChange
- XObjectChangeEventArgs
- XObjectEventHandler
- XProcessingInstruction
- XText
Lire un fichier XML à l'aide de LINQ
C #
using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
namespace LINQtoXML {
class ExampleOfXML {
static void Main(string[] args) {
string myXML = @"<Departments>
<Department>Account</Department>
<Department>Sales</Department>
<Department>Pre-Sales</Department>
<Department>Marketing</Department>
</Departments>";
XDocument xdoc = new XDocument();
xdoc = XDocument.Parse(myXML);
var result = xdoc.Element("Departments").Descendants();
foreach (XElement item in result) {
Console.WriteLine("Department Name - " + item.Value);
}
Console.WriteLine("\nPress any key to continue.");
Console.ReadKey();
}
}
}
VB
Imports System.Collections.Generic
Imports System.Linq
Imports System.Xml.Linq
Module Module1
Sub Main(ByVal args As String())
Dim myXML As String = "<Departments>" & vbCr & vbLf &
"<Department>Account</Department>" & vbCr & vbLf &
"<Department>Sales</Department>" & vbCr & vbLf &
"<Department>Pre-Sales</Department>" & vbCr & vbLf &
"<Department>Marketing</Department>" & vbCr & vbLf &
"</Departments>"
Dim xdoc As New XDocument()
xdoc = XDocument.Parse(myXML)
Dim result = xdoc.Element("Departments").Descendants()
For Each item As XElement In result
Console.WriteLine("Department Name - " + item.Value)
Next
Console.WriteLine(vbLf & "Press any key to continue.")
Console.ReadKey()
End Sub
End Module
Lorsque le code ci-dessus de C # ou VB est compilé et exécuté, il produit le résultat suivant -
Department Name - Account
Department Name - Sales
Department Name - Pre-Sales
Department Name - Marketing
Press any key to continue.
Ajouter un nouveau nœud
C #
using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
namespace LINQtoXML {
class ExampleOfXML {
static void Main(string[] args) {
string myXML = @"<Departments>
<Department>Account</Department>
<Department>Sales</Department>
<Department>Pre-Sales</Department>
<Department>Marketing</Department>
</Departments>";
XDocument xdoc = new XDocument();
xdoc = XDocument.Parse(myXML);
//Add new Element
xdoc.Element("Departments").Add(new XElement("Department", "Finance"));
//Add new Element at First
xdoc.Element("Departments").AddFirst(new XElement("Department", "Support"));
var result = xdoc.Element("Departments").Descendants();
foreach (XElement item in result) {
Console.WriteLine("Department Name - " + item.Value);
}
Console.WriteLine("\nPress any key to continue.");
Console.ReadKey();
}
}
}
VB
Imports System.Collections.Generic
Imports System.Linq
Imports System.Xml.Linq
Module Module1
Sub Main(ByVal args As String())
Dim myXML As String = "<Departments>" & vbCr & vbLf &
"<Department>Account</Department>" & vbCr & vbLf &
"<Department>Sales</Department>" & vbCr & vbLf &
"<Department>Pre-Sales</Department>" & vbCr & vbLf &
"<Department>Marketing</Department>" & vbCr & vbLf &
"</Departments>"
Dim xdoc As New XDocument()
xdoc = XDocument.Parse(myXML)
xdoc.Element("Departments").Add(New XElement("Department", "Finance"))
xdoc.Element("Departments").AddFirst(New XElement("Department", "Support"))
Dim result = xdoc.Element("Departments").Descendants()
For Each item As XElement In result
Console.WriteLine("Department Name - " + item.Value)
Next
Console.WriteLine(vbLf & "Press any key to continue.")
Console.ReadKey()
End Sub
End Module
Lorsque le code ci-dessus de C # ou VB est compilé et exécuté, il produit le résultat suivant -
Department Name - Support
Department Name - Account
Department Name - Sales
Department Name - Pre-Sales
Department Name - Marketing
Department Name - Finance
Press any key to continue.
Suppression d'un nœud particulier
C #
using System;
using System.Collections.Generic;
using System.Linq;
using System.Xml.Linq;
namespace LINQtoXML {
class ExampleOfXML {
static void Main(string[] args) {
string myXML = @"<Departments>
<Department>Support</Department>
<Department>Account</Department>
<Department>Sales</Department>
<Department>Pre-Sales</Department>
<Department>Marketing</Department>
<Department>Finance</Department>
</Departments>";
XDocument xdoc = new XDocument();
xdoc = XDocument.Parse(myXML);
//Remove Sales Department
xdoc.Descendants().Where(s =>s.Value == "Sales").Remove();
var result = xdoc.Element("Departments").Descendants();
foreach (XElement item in result) {
Console.WriteLine("Department Name - " + item.Value);
}
Console.WriteLine("\nPress any key to continue.");
Console.ReadKey();
}
}
}
VB
Imports System.Collections.Generic
Imports System.Linq
Imports System.Xml.Linq
Module Module1
Sub Main(args As String())
Dim myXML As String = "<Departments>" & vbCr & vbLf &
"<Department>Support</Department>" & vbCr & vbLf &
"<Department>Account</Department>" & vbCr & vbLf &
"<Department>Sales</Department>" & vbCr & vbLf &
"<Department>Pre-Sales</Department>" & vbCr & vbLf &
"<Department>Marketing</Department>" & vbCr & vbLf &
"<Department>Finance</Department>" & vbCr & vbLf &
"</Departments>"
Dim xdoc As New XDocument()
xdoc = XDocument.Parse(myXML)
xdoc.Descendants().Where(Function(s) s.Value = "Sales").Remove()
Dim result = xdoc.Element("Departments").Descendants()
For Each item As XElement In result
Console.WriteLine("Department Name - " + item.Value)
Next
Console.WriteLine(vbLf & "Press any key to continue.")
Console.ReadKey()
End Sub
End Module
Lorsque le code ci-dessus de C # ou VB est compilé et exécuté, il produit le résultat suivant -
Department Name - Support
Department Name - Account
Department Name - Pre-Sales
Department Name - Marketing
Department Name - Finance
Press any key to continue.