Kelas System.Xml.XmlDocument
Artikel ini menyediakan keterangan tambahan untuk dokumentasi referensi untuk API ini.
Kelas XmlDocument adalah representasi dalam memori dari dokumen XML. Ini mengimplementasikan W3C XML Document Object Model (DOM) Level 1 Core dan Core DOM Level 2.
DOM adalah singkatan dari model objek dokumen. Untuk membaca selengkapnya tentang hal itu, lihat Model Objek Dokumen XML (DOM).
Anda dapat memuat XML ke dalam DOM dengan menggunakan XmlDocument kelas , lalu membaca, memodifikasi, dan menghapus XML secara terprogram dalam dokumen.
Jika Anda ingin membuka XmlDocument kelas dan melihat cara penerapannya, lihat Sumber Referensi.
Memuat XML ke dalam model objek dokumen
Mulailah dengan dokumen XML seperti ini yang memiliki beberapa buku dalam koleksi. Ini berisi hal-hal dasar yang akan Anda temukan di dokumen XML apa pun, termasuk namespace, elemen yang mewakili data, dan atribut yang menjelaskan data.
<?xml version="1.0" encoding="utf-8"?>
<books xmlns="http://www.contoso.com/books">
<book genre="novel" ISBN="1-861001-57-8" publicationdate="1823-01-28">
<title>Pride And Prejudice</title>
<price>24.95</price>
</book>
<book genre="novel" ISBN="1-861002-30-1" publicationdate="1985-01-01">
<title>The Handmaid's Tale</title>
<price>29.95</price>
</book>
<book genre="novel" ISBN="1-861001-45-3" publicationdate="1811-01-01">
<title>Sense and Sensibility</title>
<price>19.95</price>
</book>
</books>
Selanjutnya, muat data ini ke dalam DOM sehingga Anda dapat bekerja dengannya dalam memori. Cara paling populer untuk melakukan ini adalah dengan merujuk ke file di komputer lokal Anda atau pada jaringan.
Contoh ini memuat XML dari file. Jika file tidak ada, file hanya menghasilkan beberapa XML dan memuatnya.
XmlDocument doc = new XmlDocument();
doc.PreserveWhitespace = true;
try { doc.Load("booksData.xml"); }
catch (System.IO.FileNotFoundException)
{
doc.LoadXml("<?xml version=\"1.0\"?> \n" +
"<books xmlns=\"http://www.contoso.com/books\"> \n" +
" <book genre=\"novel\" ISBN=\"1-861001-57-8\" publicationdate=\"1823-01-28\"> \n" +
" <title>Pride And Prejudice</title> \n" +
" <price>24.95</price> \n" +
" </book> \n" +
" <book genre=\"novel\" ISBN=\"1-861002-30-1\" publicationdate=\"1985-01-01\"> \n" +
" <title>The Handmaid's Tale</title> \n" +
" <price>29.95</price> \n" +
" </book> \n" +
"</books>");
}
Dim doc As XmlDocument = New XmlDocument
doc.PreserveWhitespace = True
Try
doc.Load("booksData.xml")
Catch ex As System.IO.FileNotFoundException
' If no file is found, generate some XML.
doc.LoadXml("<?xml version=""1.0""?> " & ControlChars.NewLine & _
"<books xmlns=""http://www.contoso.com/books""> " & ControlChars.NewLine & _
" <book genre=""novel"" ISBN=""1-861001-57-8"" publicationdate=""1823-01-28""> " & ControlChars.NewLine & _
" <title>Pride And Prejudice</title> " & ControlChars.NewLine & _
" <price>24.95</price> " & ControlChars.NewLine & _
" </book> " & ControlChars.NewLine & _
" <book genre=""novel"" ISBN=""1-861002-30-1"" publicationdate=""1985-01-01""> " & ControlChars.NewLine & _
" <title>The Handmaid's Tale</title> " & ControlChars.NewLine & _
" <price>29.95</price> " & ControlChars.NewLine & _
" </book> " & ControlChars.NewLine & _
"</books>")
End Try
Untuk informasi selengkapnya, lihat Membaca Dokumen XML ke dalam DOM.
Memvalidasinya terhadap skema
Mulailah dengan skema XML seperti ini. Skema ini menentukan jenis data dalam XML dan atribut mana yang diperlukan.
<?xml version="1.0" encoding="utf-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
attributeFormDefault="unqualified"
elementFormDefault="qualified"
targetNamespace="http://www.contoso.com/books">
<xs:element name="books">
<xs:complexType>
<xs:sequence>
<xs:element maxOccurs="unbounded" name="book">
<xs:complexType>
<xs:sequence>
<xs:element name="title" type="xs:string" />
<xs:element name="price" type="xs:decimal" />
</xs:sequence>
<xs:attribute name="genre" type="xs:string" use="required" />
<xs:attribute name="ISBN" type="xs:string" use="required" />
<xs:attribute name="publicationdate" type="xs:date" use="required" />
</xs:complexType>
</xs:element>
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>
Buat XmlReader objek dengan menggunakan skema Anda, lalu muat objek tersebut ke dalam DOM. Buat penanganan aktivitas yang dijalankan saat kode mencoba memodifikasi file XML Anda dengan cara yang melanggar aturan skema.
Blok kode ini menunjukkan metode pembantu yang melakukan semua ini.
//************************************************************************************
//
// Helper method that generates an XML string.
//
//************************************************************************************
private string generateXMLString()
{
string xml = "<?xml version=\"1.0\"?> \n" +
"<books xmlns=\"http://www.contoso.com/books\"> \n" +
" <book genre=\"novel\" ISBN=\"1-861001-57-8\" publicationdate=\"1823-01-28\"> \n" +
" <title>Pride And Prejudice</title> \n" +
" <price>24.95</price> \n" +
" </book> \n" +
" <book genre=\"novel\" ISBN=\"1-861002-30-1\" publicationdate=\"1985-01-01\"> \n" +
" <title>The Handmaid's Tale</title> \n" +
" <price>29.95</price> \n" +
" </book> \n" +
" <book genre=\"novel\" ISBN=\"1-861001-45-3\" publicationdate=\"1811-01-01\"> \n" +
" <title>Sense and Sensibility</title> \n" +
" <price>19.95</price> \n" +
" </book> \n" +
"</books>";
return xml;
}
//************************************************************************************
//
// Associate the schema with XML. Then, load the XML and validate it against
// the schema.
//
//************************************************************************************
public XmlDocument LoadDocumentWithSchemaValidation(bool generateXML, bool generateSchema)
{
XmlReader reader = null;
XmlReaderSettings settings = new XmlReaderSettings();
// Helper method to retrieve schema.
XmlSchema schema = getSchema(generateSchema);
settings.Schemas.Add(schema);
settings.ValidationEventHandler += ValidationCallback;
settings.ValidationFlags =
settings.ValidationFlags | XmlSchemaValidationFlags.ReportValidationWarnings;
settings.ValidationType = ValidationType.Schema;
if (!generateXML)
{
try
{
reader = XmlReader.Create("booksData.xml", settings);
}
catch (FileNotFoundException ex)
{
Console.WriteLine(
$"XML file not found so generating: {ex.Message}");
generateXML = true;
}
}
if (generateXML)
{
string xml = generateXMLString();
StringReader stringReader = new StringReader(xml);
reader = XmlReader.Create(stringReader, settings);
}
XmlDocument doc = new XmlDocument();
doc.PreserveWhitespace = true;
doc.Load(reader);
reader.Close();
return doc;
}
//************************************************************************************
//
// Helper method that generates an XML Schema.
//
//************************************************************************************
private string generateXMLSchema()
{
string xmlSchema =
"<?xml version=\"1.0\" encoding=\"utf-8\"?> " +
"<xs:schema attributeFormDefault=\"unqualified\" " +
"elementFormDefault=\"qualified\" targetNamespace=\"http://www.contoso.com/books\" " +
"xmlns:xs=\"http://www.w3.org/2001/XMLSchema\"> " +
"<xs:element name=\"books\"> " +
"<xs:complexType> " +
"<xs:sequence> " +
"<xs:element maxOccurs=\"unbounded\" name=\"book\"> " +
"<xs:complexType> " +
"<xs:sequence> " +
"<xs:element name=\"title\" type=\"xs:string\" /> " +
"<xs:element name=\"price\" type=\"xs:decimal\" /> " +
"</xs:sequence> " +
"<xs:attribute name=\"genre\" type=\"xs:string\" use=\"required\" /> " +
"<xs:attribute name=\"publicationdate\" type=\"xs:date\" use=\"required\" /> " +
"<xs:attribute name=\"ISBN\" type=\"xs:string\" use=\"required\" /> " +
"</xs:complexType> " +
"</xs:element> " +
"</xs:sequence> " +
"</xs:complexType> " +
"</xs:element> " +
"</xs:schema> ";
return xmlSchema;
}
//************************************************************************************
//
// Helper method that gets a schema
//
//************************************************************************************
private XmlSchema getSchema(bool generateSchema)
{
XmlSchemaSet xs = new XmlSchemaSet();
XmlSchema schema = null;
if (!generateSchema)
{
try
{
schema = xs.Add("http://www.contoso.com/books", "booksData.xsd");
}
catch (FileNotFoundException ex)
{
Console.WriteLine(
$"XSD file not found so generating: {ex.Message}");
generateSchema = true;
}
}
if (generateSchema)
{
string xmlSchemaString = generateXMLSchema();
StringReader stringReader = new StringReader(xmlSchemaString);
XmlReader reader = XmlReader.Create(stringReader);
schema = xs.Add("http://www.contoso.com/books", reader);
}
return schema;
}
//************************************************************************************
//
// Helper method to validate the XML against the schema.
//
//************************************************************************************
private void validateXML(bool generateSchema, XmlDocument doc)
{
if (doc.Schemas.Count == 0)
{
// Helper method to retrieve schema.
XmlSchema schema = getSchema(generateSchema);
doc.Schemas.Add(schema);
}
// Use a callback to validate the XML node against the schema.
doc.Validate(ValidationCallback);
}
//************************************************************************************
//
// Event handler that is raised when XML doesn't validate against the schema.
//
//************************************************************************************
void ValidationCallback(object sender,
System.Xml.Schema.ValidationEventArgs e)
{
if (e.Severity == XmlSeverityType.Warning)
{
Console.WriteLine
("The following validation warning occurred: " + e.Message);
}
else if (e.Severity == XmlSeverityType.Error)
{
Console.WriteLine
("The following critical validation errors occurred: " + e.Message);
}
}
'************************************************************************************
'
' Associate the schema with XML. Then, load the XML and validate it against
' the schema.
'
'************************************************************************************
Public Function LoadDocumentWithSchemaValidation(ByVal generateXML As Boolean, ByVal generateSchema As Boolean) As XmlDocument
Dim reader As XmlReader
Dim settings As XmlReaderSettings = New XmlReaderSettings
' Helper method to retrieve schema.
Dim schema As XmlSchema = getSchema(generateSchema)
If (schema Is Nothing) Then
Return Nothing
End If
settings.Schemas.Add(schema)
AddHandler settings.ValidationEventHandler, AddressOf settings_ValidationEventHandler
settings.ValidationFlags = (settings.ValidationFlags Or XmlSchemaValidationFlags.ReportValidationWarnings)
settings.ValidationType = ValidationType.Schema
Try
reader = XmlReader.Create("booksData.xml", settings)
Catch ex As System.IO.FileNotFoundException
If generateXML Then
Dim xml As String = generateXMLString()
Dim byteArray() As Byte = Encoding.UTF8.GetBytes(xml)
Dim stream As MemoryStream = New MemoryStream(byteArray)
reader = XmlReader.Create(stream, settings)
Else
Return Nothing
End If
End Try
Dim doc As XmlDocument = New XmlDocument
doc.PreserveWhitespace = True
doc.Load(reader)
reader.Close()
Return doc
End Function
'************************************************************************************
'
' Helper method that generates an XML Schema.
'
'************************************************************************************
Private Function generateXMLSchema() As String
Dim generatedXmlSchema As String = "<?xml version=""1.0"" encoding=""utf-8""?> " & _
"<xs:schema attributeFormDefault=""unqualified"" " & _
"elementFormDefault=""qualified"" targetNamespace=""http://www.contoso.com/books"" " & _
"xmlns:xs=""http://www.w3.org/2001/XMLSchema""> " & _
"<xs:element name=""books""> " & _
"<xs:complexType> " & _
"<xs:sequence> " & _
"<xs:element maxOccurs=""unbounded"" name=""book""> " & _
"<xs:complexType> " & _
"<xs:sequence> " & _
"<xs:element name=""title"" type=""xs:string"" /> " & _
"<xs:element name=""price"" type=""xs:decimal"" /> " & _
"</xs:sequence> " & _
"<xs:attribute name=""genre"" type=""xs:string"" use=""required"" /> " & _
"<xs:attribute name=""publicationdate"" type=""xs:date"" use=""required"" /> " & _
"<xs:attribute name=""ISBN"" type=""xs:string"" use=""required"" /> " & _
"</xs:complexType> " & _
"</xs:element> " & _
"</xs:sequence> " & _
"</xs:complexType> " & _
"</xs:element> " & _
"</xs:schema> "
Return generatedXmlSchema
End Function
'************************************************************************************
'
' Helper method that gets a schema
'
'************************************************************************************
Private Function getSchema(ByVal generateSchema As Boolean) As XmlSchema
Dim xs As XmlSchemaSet = New XmlSchemaSet
Dim schema As XmlSchema
Try
schema = xs.Add("http://www.contoso.com/books", "booksData.xsd")
Catch ex As System.IO.FileNotFoundException
If generateSchema Then
Dim xmlSchemaString As String = generateXMLSchema()
Dim byteArray() As Byte = Encoding.UTF8.GetBytes(xmlSchemaString)
Dim stream As MemoryStream = New MemoryStream(byteArray)
Dim reader As XmlReader = XmlReader.Create(stream)
schema = xs.Add("http://www.contoso.com/books", reader)
Else
Return Nothing
End If
End Try
Return schema
End Function
'************************************************************************************
'
' Helper method to validate the XML against the schema.
'
'************************************************************************************
Private Sub validateXML(ByVal generateSchema As Boolean, ByVal doc As XmlDocument)
If (doc.Schemas.Count = 0) Then
' Helper method to retrieve schema.
Dim schema As XmlSchema = getSchema(generateSchema)
doc.Schemas.Add(schema)
End If
' Use an event handler to validate the XML node against the schema.
doc.Validate(AddressOf settings_ValidationEventHandler)
End Sub
'************************************************************************************
'
' Event handler that is raised when XML doesn't validate against the schema.
'
'************************************************************************************
Private Sub settings_ValidationEventHandler(ByVal sender As Object, ByVal e As System.Xml.Schema.ValidationEventArgs)
If (e.Severity = XmlSeverityType.Warning) Then
System.Windows.Forms.MessageBox.Show(("The following validation warning occurred: " & e.Message))
ElseIf (e.Severity = XmlSeverityType.Error) Then
System.Windows.Forms.MessageBox.Show(("The following critical validation errors occurred: " & e.Message))
Dim objectType As Type = sender.GetType
End If
End Sub
Untuk informasi selengkapnya, lihat Memvalidasi Dokumen XML di DOM.
Menavigasi pohon dokumen
Anda dapat menggunakan properti untuk menavigasi di sekitar dokumen XML. Tetapi sebelum Anda menggunakan salah satu dari mereka, mari kita tinjau beberapa istilah dengan cepat. Dokumen Anda terdiri dari simpul. Setiap simpul memiliki satu simpul induk tepat di atasnya. Satu-satunya simpul yang tidak memiliki simpul induk adalah akar dokumen, karena merupakan simpul tingkat atas. Sebagian besar simpul dapat memiliki simpul anak , yang merupakan simpul tepat di bawahnya. Node yang berada di tingkat yang sama adalah saudara kandung.
Contoh berikut menunjukkan kepada Anda cara mendapatkan simpul akar, melompat ke simpul anak pertama dari simpul akar, mengakses salah satu simpul anaknya, kembali ke simpul induk, lalu menavigasi di seluruh simpul saudara.
Mulai dengan simpul akar
Contoh ini mendapatkan simpul akar lalu menggunakan simpul tersebut untuk menghasilkan konten dokumen ke konsol.
using System;
using System.IO;
using System.Xml;
public class Sample
{
public static void Main()
{
//Create the XmlDocument.
XmlDocument doc = new XmlDocument();
doc.LoadXml("<?xml version='1.0' ?>" +
"<book genre='novel' ISBN='1-861001-57-5'>" +
"<title>Pride And Prejudice</title>" +
"</book>");
//Display the document element.
Console.WriteLine(doc.DocumentElement.OuterXml);
}
}
Option Strict On
Option Explicit On
Imports System.Xml
Public Class ElementSample
Public Shared Sub Main()
'Create the XmlDocument.
Dim doc As New XmlDocument()
doc.LoadXml("<?xml version='1.0' ?>" &
"<book genre='novel' ISBN='1-861001-57-5'>" &
"<title>Pride And Prejudice</title>" &
"</book>")
'Display the document element.
Console.WriteLine(doc.DocumentElement.OuterXml)
End Sub
End Class
Mendapatkan simpul anak
Contoh ini melompat ke simpul anak pertama dari simpul akar dan kemudian melakukan iterasi melalui simpul anak dari simpul tersebut jika ada.
using System;
using System.Xml;
public class Sample2
{
public static void Main()
{
XmlDocument doc = new XmlDocument();
doc.LoadXml("<book ISBN='1-861001-57-5'>" +
"<title>Pride And Prejudice</title>" +
"<price>19.95</price>" +
"</book>");
XmlNode root = doc.FirstChild;
//Display the contents of the child nodes.
if (root.HasChildNodes)
{
for (int i = 0; i < root.ChildNodes.Count; i++)
{
Console.WriteLine(root.ChildNodes[i].InnerText);
}
}
}
}
Option Strict
Option Explicit
Imports System.IO
Imports System.Xml
Public Class Sample
Public Shared Sub Main()
Dim doc As New XmlDocument()
doc.LoadXml("<book ISBN='1-861001-57-5'>" & _
"<title>Pride And Prejudice</title>" & _
"<price>19.95</price>" & _
"</book>")
Dim root As XmlNode = doc.FirstChild
'Display the contents of the child nodes.
If root.HasChildNodes Then
Dim i As Integer
For i = 0 To root.ChildNodes.Count - 1
Console.WriteLine(root.ChildNodes(i).InnerText)
Next i
End If
End Sub
End Class
Kembali ke simpul induk
Gunakan properti ParentNode.
Lihat simpul anak terakhir
Contoh ini menulis harga buku ke konsol. Simpul harga adalah anak terakhir dari simpul buku.
using System;
using System.Xml;
public class Sample3
{
public static void Main()
{
XmlDocument doc = new XmlDocument();
doc.LoadXml("<book ISBN='1-861001-57-5'>" +
"<title>Pride And Prejudice</title>" +
"<price>19.95</price>" +
"</book>");
XmlNode root = doc.FirstChild;
Console.WriteLine("Display the price element...");
Console.WriteLine(root.LastChild.OuterXml);
}
}
Option Explicit On
Option Strict On
Imports System.Xml
Public Class LastChildSample
Public Shared Sub Main()
Dim doc As New XmlDocument()
doc.LoadXml("<book ISBN='1-861001-57-5'>" &
"<title>Pride And Prejudice</title>" &
"<price>19.95</price>" &
"</book>")
Dim root As XmlNode = doc.FirstChild
Console.WriteLine("Display the price element...")
Console.WriteLine(root.LastChild.OuterXml)
End Sub
End Class
Menavigasi ke depan di seluruh saudara kandung
Contoh ini bergerak maju dari buku ke buku. Simpul buku adalah saudara kandung satu sama lain.
using System;
using System.Xml;
public class Sample4
{
public static void Main()
{
XmlDocument doc = new XmlDocument();
doc.Load("books.xml");
XmlNode currNode = doc.DocumentElement.FirstChild;
Console.WriteLine("First book...");
Console.WriteLine(currNode.OuterXml);
XmlNode nextNode = currNode.NextSibling;
Console.WriteLine("\r\nSecond book...");
Console.WriteLine(nextNode.OuterXml);
}
}
Imports System.Xml
Public Class NextSiblingSample
Public Shared Sub Main()
Dim doc As XmlDocument = New XmlDocument()
doc.Load("books.xml")
Dim currNode As XmlNode = doc.DocumentElement.FirstChild
Console.WriteLine("First book...")
Console.WriteLine(currNode.OuterXml)
Dim nextNode As XmlNode = currNode.NextSibling
Console.WriteLine(ControlChars.Lf + "Second book...")
Console.WriteLine(nextNode.OuterXml)
End Sub
End Class
Menavigasi mundur melintasi saudara kandung
Contoh ini bergerak mundur dari buku ke buku.
using System;
using System.Xml;
public class Sample {
public static void Main() {
XmlDocument doc = new XmlDocument();
doc.Load("books.xml");
XmlNode lastNode = doc.DocumentElement.LastChild;
Console.WriteLine("Last book...");
Console.WriteLine(lastNode.OuterXml);
XmlNode prevNode = lastNode.PreviousSibling;
Console.WriteLine("\r\nPrevious book...");
Console.WriteLine(prevNode.OuterXml);
}
}
Imports System.Xml
Public Class Sample5
Public Shared Sub Main()
Dim doc As XmlDocument = New XmlDocument()
doc.Load("books.xml")
Dim lastNode As XmlNode = doc.DocumentElement.LastChild
Console.WriteLine("Last book...")
Console.WriteLine(lastNode.OuterXml)
Dim prevNode As XmlNode = lastNode.PreviousSibling
Console.WriteLine(ControlChars.Lf + "Previous book...")
Console.WriteLine(prevNode.OuterXml)
End Sub
End Class
Menemukan simpul
Cara paling populer untuk menemukan satu atau beberapa simpul data adalah dengan menggunakan string kueri XPath, tetapi ada juga metode yang tidak memerlukannya.
Mendapatkan satu simpul
Contoh ini menemukan buku dengan menggunakan nomor ISBN.
public XmlNode GetBook(string uniqueAttribute, XmlDocument doc)
{
XmlNamespaceManager nsmgr = new XmlNamespaceManager(doc.NameTable);
nsmgr.AddNamespace("bk", "http://www.contoso.com/books");
string xPathString = "//bk:books/bk:book[@ISBN='" + uniqueAttribute + "']";
XmlNode xmlNode = doc.DocumentElement.SelectSingleNode(xPathString, nsmgr);
return xmlNode;
}
Public Function GetBook(ByVal uniqueAttribute As String, ByVal doc As XmlDocument) As XmlNode
Dim nsmgr As XmlNamespaceManager = New XmlNamespaceManager(doc.NameTable)
nsmgr.AddNamespace("bk", "http://www.contoso.com/books")
Dim xPathString As String = ("//bk:books/bk:book[@ISBN='" _
& (uniqueAttribute & "']"))
Dim xmlNode As XmlNode = doc.DocumentElement.SelectSingleNode(xPathString, nsmgr)
Return xmlNode
End Function
String yang digunakan dalam contoh ini adalah kueri Xpath. Anda dapat menemukan lebih banyak contohnya di contoh XPath.
Anda juga dapat menggunakan GetElementById untuk mengambil simpul. Untuk menggunakan pendekatan ini, Anda harus menentukan ID dalam deklarasi definisi jenis dokumen file XML Anda.
Setelah mendapatkan simpul, Anda mendapatkan nilai atribut atau simpul anak. Contoh ini melakukannya dengan simpul buku.
public void GetBookInformation(ref string title, ref string ISBN, ref string publicationDate,
ref string price, ref string genre, XmlNode book)
{
XmlElement bookElement = (XmlElement)book;
// Get the attributes of a book.
XmlAttribute attr = bookElement.GetAttributeNode("ISBN");
ISBN = attr.InnerXml;
attr = bookElement.GetAttributeNode("genre");
genre = attr.InnerXml;
attr = bookElement.GetAttributeNode("publicationdate");
publicationDate = attr.InnerXml;
// Get the values of child elements of a book.
title = bookElement["title"].InnerText;
price = bookElement["price"].InnerText;
}
Public Sub GetBookInformation(ByRef title As String, ByRef ISBN As String, ByRef publicationDate As String, ByRef price As String, ByRef genre As String, ByVal book As XmlNode)
Dim bookElement As XmlElement = CType(book, XmlElement)
' Get the attributes of a book.
Dim attr As XmlAttribute = bookElement.GetAttributeNode("ISBN")
ISBN = attr.InnerXml
attr = bookElement.GetAttributeNode("genre")
genre = attr.InnerXml
attr = bookElement.GetAttributeNode("publicationdate")
publicationDate = attr.InnerXml
' Get the values of child elements of a book.
title = bookElement("title").InnerText
price = bookElement("price").InnerText
End Sub
Mendapatkan koleksi simpul
Contoh ini memilih semua buku di mana nama belakang penulis adalah Austen, lalu mengubah harga buku-buku tersebut.
using System;
using System.Xml;
public class Sample6
{
public static void Main()
{
XmlDocument doc = new XmlDocument();
doc.Load("booksort.xml");
XmlNodeList nodeList;
XmlNode root = doc.DocumentElement;
nodeList = root.SelectNodes("descendant::book[author/last-name='Austen']");
//Change the price on the books.
foreach (XmlNode book in nodeList)
{
book.LastChild.InnerText = "15.95";
}
Console.WriteLine("Display the modified XML document....");
doc.Save(Console.Out);
}
}
Imports System.IO
Imports System.Xml
public class Sample
public shared sub Main()
'Create the XmlDocument.
Dim doc as XmlDocument = new XmlDocument()
doc.Load("booksort.xml")
Dim book as XmlNode
Dim nodeList as XmlNodeList
Dim root as XmlNode = doc.DocumentElement
nodeList=root.SelectNodes("descendant::book[author/last-name='Austen']")
'Change the price on the books.
for each book in nodeList
book.LastChild.InnerText="15.95"
next
Console.WriteLine("Display the modified XML document....")
doc.Save(Console.Out)
end sub
end class
Anda juga bisa mendapatkan koleksi simpul dengan menggunakan nama simpul. Misalnya, contoh ini mendapatkan koleksi semua judul buku.
using System;
using System.Xml;
public class Sample1
{
public static void Main()
{
//Create the XmlDocument.
XmlDocument doc = new XmlDocument();
doc.Load("books.xml");
//Display all the book titles.
XmlNodeList elemList = doc.GetElementsByTagName("title");
for (int i = 0; i < elemList.Count; i++)
{
Console.WriteLine(elemList[i].InnerXml);
}
}
}
Option Explicit On
Option Strict On
Imports System.Xml
Public Class TagSample
Public Shared Sub Main()
'Create the XmlDocument.
Dim doc As New XmlDocument()
doc.Load("books.xml")
'Display all the book titles.
Dim elemList As XmlNodeList = doc.GetElementsByTagName("title")
Dim i As Integer
For i = 0 To elemList.Count - 1
Console.WriteLine(elemList(i).InnerXml)
Next i
End Sub
End Class
Untuk informasi selengkapnya, lihat Memilih Simpul Menggunakan Navigasi XPath.
Mengedit simpul
Contoh ini mengedit simpul buku dan atributnya.
public void editBook(string title, string ISBN, string publicationDate,
string genre, string price, XmlNode book, bool validateNode, bool generateSchema)
{
XmlElement bookElement = (XmlElement)book;
// Get the attributes of a book.
bookElement.SetAttribute("ISBN", ISBN);
bookElement.SetAttribute("genre", genre);
bookElement.SetAttribute("publicationdate", publicationDate);
// Get the values of child elements of a book.
bookElement["title"].InnerText = title;
bookElement["price"].InnerText = price;
if (validateNode)
{
validateXML(generateSchema, bookElement.OwnerDocument);
}
}
Public Sub editBook(ByVal title As String, ByVal ISBN As String,
ByVal publicationDate As String, ByVal genre As String,
ByVal price As String, ByVal book As XmlNode, ByVal validateNode As Boolean,
ByVal generateSchema As Boolean)
Dim bookElement As XmlElement = CType(book, XmlElement)
' Get the attributes of a book.
bookElement.SetAttribute("ISBN", ISBN)
bookElement.SetAttribute("genre", genre)
bookElement.SetAttribute("publicationdate", publicationDate)
' Get the values of child elements of a book.
bookElement("title").InnerText = title
bookElement("price").InnerText = price
If validateNode Then
validateXML(generateSchema, bookElement.OwnerDocument)
End If
End Sub
Untuk informasi selengkapnya, lihat Memodifikasi Simpul, Konten, dan Nilai dalam Dokumen XML.
Menambahkan node
Untuk menambahkan simpul, gunakan CreateElement metode atau CreateNode metode .
Untuk menambahkan simpul data seperti buku, gunakan metode .CreateElement
Untuk jenis node lain seperti komentar, node spasi kosong, atau node CDATA, gunakan metode .CreateNode
Contoh ini membuat simpul buku, menambahkan atribut ke simpul tersebut, lalu menambahkan simpul tersebut ke dokumen.
public XmlElement AddNewBook(string genre, string ISBN, string misc,
string title, string price, XmlDocument doc)
{
// Create a new book element.
XmlElement bookElement = doc.CreateElement("book", "http://www.contoso.com/books");
// Create attributes for book and append them to the book element.
XmlAttribute attribute = doc.CreateAttribute("genre");
attribute.Value = genre;
bookElement.Attributes.Append(attribute);
attribute = doc.CreateAttribute("ISBN");
attribute.Value = ISBN;
bookElement.Attributes.Append(attribute);
attribute = doc.CreateAttribute("publicationdate");
attribute.Value = misc;
bookElement.Attributes.Append(attribute);
// Create and append a child element for the title of the book.
XmlElement titleElement = doc.CreateElement("title");
titleElement.InnerText = title;
bookElement.AppendChild(titleElement);
// Introduce a newline character so that XML is nicely formatted.
bookElement.InnerXml =
bookElement.InnerXml.Replace(titleElement.OuterXml,
"\n " + titleElement.OuterXml + " \n ");
// Create and append a child element for the price of the book.
XmlElement priceElement = doc.CreateElement("price");
priceElement.InnerText= price;
bookElement.AppendChild(priceElement);
// Introduce a newline character so that XML is nicely formatted.
bookElement.InnerXml =
bookElement.InnerXml.Replace(priceElement.OuterXml, priceElement.OuterXml + " \n ");
return bookElement;
}
Public Function AddNewBook(ByVal genre As String, ByVal ISBN As String, ByVal misc As String, ByVal title As String, ByVal price As String, ByVal doc As XmlDocument) As XmlElement
' Create a new book element.
Dim bookElement As XmlElement = doc.CreateElement("book", "http://www.contoso.com/books")
' Create attributes for book and append them to the book element.
Dim attribute As XmlAttribute = doc.CreateAttribute("genre")
attribute.Value = genre
bookElement.Attributes.Append(attribute)
attribute = doc.CreateAttribute("ISBN")
attribute.Value = ISBN
bookElement.Attributes.Append(attribute)
attribute = doc.CreateAttribute("publicationdate")
attribute.Value = misc
bookElement.Attributes.Append(attribute)
' Create and append a child element for the title of the book.
Dim titleElement As XmlElement = doc.CreateElement("title")
titleElement.InnerText = title
bookElement.AppendChild(titleElement)
' Introduce a newline character so that XML is nicely formatted.
bookElement.InnerXml = bookElement.InnerXml.Replace(titleElement.OuterXml, _
"\n " & titleElement.OuterXml & " " & ControlChars.NewLine + " ")
' Create and append a child element for the price of the book.
Dim priceElement As XmlElement = doc.CreateElement("price")
priceElement.InnerText = price
bookElement.AppendChild(priceElement)
' Introduce a newline character so that XML is nicely formatted.
bookElement.InnerXml = bookElement.InnerXml.Replace(priceElement.OuterXml,
(priceElement.OuterXml & " " & ControlChars.NewLine & " "))
Return bookElement
End Function
Untuk informasi selengkapnya, lihat Menyisipkan Simpul ke dalam Dokumen XML.
Menghapus simpul
Untuk menghapus simpul, gunakan RemoveChild metode .
Contoh ini menghapus buku dari dokumen dan spasi kosong apa pun yang muncul tepat sebelum simpul buku.
public void deleteBook(XmlNode book)
{
XmlNode prevNode = book.PreviousSibling;
book.OwnerDocument.DocumentElement.RemoveChild(book);
if (prevNode.NodeType == XmlNodeType.Whitespace ||
prevNode.NodeType == XmlNodeType.SignificantWhitespace)
{
prevNode.OwnerDocument.DocumentElement.RemoveChild(prevNode);
}
}
Public Sub deleteBook(ByVal book As XmlNode)
Dim prevNode As XmlNode = book.PreviousSibling
book.OwnerDocument.DocumentElement.RemoveChild(book)
If ((prevNode.NodeType = XmlNodeType.Whitespace) _
OrElse (prevNode.NodeType = XmlNodeType.SignificantWhitespace)) Then
prevNode.OwnerDocument.DocumentElement.RemoveChild(prevNode)
End If
End Sub
Untuk informasi selengkapnya, lihat Menghapus Simpul, Konten, dan Nilai dari Dokumen XML.
Simpul posisi
Anda dapat memilih di mana Anda ingin node muncul di dokumen Anda dengan menggunakan InsertBefore metode dan InsertAfter .
Contoh ini menunjukkan dua metode pembantu. Salah satunya memindahkan simpul yang lebih tinggi dalam daftar. Yang lain memindahkan node lebih rendah.
Metode ini dapat digunakan dalam aplikasi yang memungkinkan pengguna untuk memindahkan buku ke atas dan ke bawah dalam daftar buku. Ketika pengguna memilih buku dan menekan tombol atas atau bawah, kode Anda dapat memanggil metode seperti ini untuk memposisikan node buku yang sesuai sebelum atau setelah node buku lainnya.
//************************************************************************************
//
// Summary: Move elements up in the XML.
//
//
//************************************************************************************
public void MoveElementUp(XmlNode book)
{
XmlNode previousNode = book.PreviousSibling;
while (previousNode != null && (previousNode.NodeType != XmlNodeType.Element))
{
previousNode = previousNode.PreviousSibling;
}
if (previousNode != null)
{
XmlNode newLineNode = book.NextSibling;
book.OwnerDocument.DocumentElement.RemoveChild(book);
if (newLineNode.NodeType == XmlNodeType.Whitespace |
newLineNode.NodeType == XmlNodeType.SignificantWhitespace)
{
newLineNode.OwnerDocument.DocumentElement.RemoveChild(newLineNode);
}
InsertBookElement((XmlElement)book, Constants.positionAbove,
previousNode, false, false);
}
}
//************************************************************************************
//
// Summary: Move elements down in the XML.
//
//
//************************************************************************************
public void MoveElementDown(XmlNode book)
{
// Walk backwards until we find an element - ignore text nodes
XmlNode NextNode = book.NextSibling;
while (NextNode != null && (NextNode.NodeType != XmlNodeType.Element))
{
NextNode = NextNode.NextSibling;
}
if (NextNode != null)
{
XmlNode newLineNode = book.PreviousSibling;
book.OwnerDocument.DocumentElement.RemoveChild(book);
if (newLineNode.NodeType == XmlNodeType.Whitespace |
newLineNode.NodeType == XmlNodeType.SignificantWhitespace)
{
newLineNode.OwnerDocument.DocumentElement.RemoveChild(newLineNode);
}
InsertBookElement((XmlElement)book, Constants.positionBelow,
NextNode, false, false);
}
}
'************************************************************************************
'
' Summary: Move elements up in the XML.
'
'
'************************************************************************************
Public Sub MoveElementUp(ByVal book As XmlNode)
Dim previousNode As XmlNode = book.PreviousSibling
While ((Not (previousNode) Is Nothing) _
AndAlso (previousNode.NodeType <> XmlNodeType.Element))
previousNode = previousNode.PreviousSibling
End While
If (Not (previousNode) Is Nothing) Then
Dim newLineNode As XmlNode = book.NextSibling
book.OwnerDocument.DocumentElement.RemoveChild(book)
If ((newLineNode.NodeType = XmlNodeType.Whitespace) _
Or (newLineNode.NodeType = XmlNodeType.SignificantWhitespace)) Then
newLineNode.OwnerDocument.DocumentElement.RemoveChild(newLineNode)
End If
InsertBookElement(CType(book, XmlElement), Constants.positionAbove,
previousNode, False, False)
End If
End Sub
'************************************************************************************
'
' Summary: Move elements down in the XML.
'
'
'************************************************************************************
Public Sub MoveElementDown(ByVal book As XmlNode)
' Walk backwards until we find an element - ignore text nodes
Dim NextNode As XmlNode = book.NextSibling
While ((Not (NextNode) Is Nothing) _
AndAlso (NextNode.NodeType <> XmlNodeType.Element))
NextNode = NextNode.NextSibling
End While
If (Not (NextNode) Is Nothing) Then
Dim newLineNode As XmlNode = book.PreviousSibling
book.OwnerDocument.DocumentElement.RemoveChild(book)
If ((newLineNode.NodeType = XmlNodeType.Whitespace) _
Or (newLineNode.NodeType = XmlNodeType.SignificantWhitespace)) Then
newLineNode.OwnerDocument.DocumentElement.RemoveChild(newLineNode)
End If
InsertBookElement(CType(book, XmlElement), Constants.positionBelow,
NextNode, False, False)
End If
End Sub
Berkolaborasi dengan kami di GitHub
Sumber untuk konten ini dapat ditemukan di GitHub, yang juga dapat Anda gunakan untuk membuat dan meninjau masalah dan menarik permintaan. Untuk informasi selengkapnya, lihat panduan kontributor kami.
Saran dan Komentar
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