XmlTextWriter.WriteStartElement(String, String, String) Метод
Определение
Важно!
Некоторые сведения относятся к предварительной версии продукта, в которую до выпуска могут быть внесены существенные изменения. Майкрософт не предоставляет никаких гарантий, явных или подразумеваемых, относительно приведенных здесь сведений.
Записывает указанный открывающий тег и связывает его с заданным пространством имен и префиксом.
public:
override void WriteStartElement(System::String ^ prefix, System::String ^ localName, System::String ^ ns);
public override void WriteStartElement (string? prefix, string localName, string? ns);
public override void WriteStartElement (string prefix, string localName, string ns);
override this.WriteStartElement : string * string * string -> unit
Public Overrides Sub WriteStartElement (prefix As String, localName As String, ns As String)
Параметры
- prefix
- String
Префикс пространства имен элемента.
- localName
- String
Локальное имя элемента.
- ns
- String
URI пространства имен, связываемый с элементом. Если пространство имен уже находится в области видимости и с ним связан префикс, средство записи автоматически запишет этот префикс.
Исключения
Модуль записи закрыт.
Примеры
В следующем примере записывается книга.
#using <System.Xml.dll>
using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
String^ filename = "sampledata.xml";
XmlTextWriter^ writer = gcnew XmlTextWriter( filename, nullptr );
//Use indenting for readability.
writer->Formatting = Formatting::Indented;
writer->WriteComment( "sample XML fragment" );
//Write an element (this one is the root).
writer->WriteStartElement( "bookstore" );
//Write the namespace declaration.
writer->WriteAttributeString( "xmlns", "bk", nullptr, "urn:samples" );
writer->WriteStartElement( "book" );
//Lookup the prefix and then write the ISBN attribute.
String^ prefix = writer->LookupPrefix( "urn:samples" );
writer->WriteStartAttribute( prefix, "ISBN", "urn:samples" );
writer->WriteString( "1-861003-78" );
writer->WriteEndAttribute();
//Write the title.
writer->WriteStartElement( "title" );
writer->WriteString( "The Handmaid's Tale" );
writer->WriteEndElement();
//Write the price.
writer->WriteElementString( "price", "19.95" );
//Write the style element.
writer->WriteStartElement( prefix, "style", "urn:samples" );
writer->WriteString( "hardcover" );
writer->WriteEndElement();
//Write the end tag for the book element.
writer->WriteEndElement();
//Write the close tag for the root element.
writer->WriteEndElement();
//Write the XML to file and close the writer.
writer->Flush();
writer->Close();
//Read the file back in and parse to ensure well formed XML.
XmlDocument^ doc = gcnew XmlDocument;
//Preserve white space for readability.
doc->PreserveWhitespace = true;
//Load the file
doc->Load( filename );
//Write the XML content to the console.
Console::Write( doc->InnerXml );
}
using System;
using System.IO;
using System.Xml;
public class Sample
{
private const string filename = "sampledata.xml";
public static void Main()
{
XmlTextWriter writer = new XmlTextWriter (filename, null);
//Use indenting for readability.
writer.Formatting = Formatting.Indented;
writer.WriteComment("sample XML fragment");
//Write an element (this one is the root).
writer.WriteStartElement("bookstore");
//Write the namespace declaration.
writer.WriteAttributeString("xmlns", "bk", null, "urn:samples");
writer.WriteStartElement("book");
//Lookup the prefix and then write the ISBN attribute.
string prefix = writer.LookupPrefix("urn:samples");
writer.WriteStartAttribute(prefix, "ISBN", "urn:samples");
writer.WriteString("1-861003-78");
writer.WriteEndAttribute();
//Write the title.
writer.WriteStartElement("title");
writer.WriteString("The Handmaid's Tale");
writer.WriteEndElement();
//Write the price.
writer.WriteElementString("price", "19.95");
//Write the style element.
writer.WriteStartElement(prefix, "style", "urn:samples");
writer.WriteString("hardcover");
writer.WriteEndElement();
//Write the end tag for the book element.
writer.WriteEndElement();
//Write the close tag for the root element.
writer.WriteEndElement();
//Write the XML to file and close the writer.
writer.Flush();
writer.Close();
//Read the file back in and parse to ensure well formed XML.
XmlDocument doc = new XmlDocument();
//Preserve white space for readability.
doc.PreserveWhitespace = true;
//Load the file
doc.Load(filename);
//Write the XML content to the console.
Console.Write(doc.InnerXml);
}
}
Option Strict
Option Explicit
Imports System.IO
Imports System.Xml
Public Class Sample
Private Shared filename As String = "sampledata.xml"
Public Shared Sub Main()
Dim writer As New XmlTextWriter(filename, Nothing)
'Use indenting for readability.
writer.Formatting = Formatting.Indented
writer.WriteComment("sample XML fragment")
'Write an element (this one is the root).
writer.WriteStartElement("bookstore")
'Write the namespace declaration.
writer.WriteAttributeString("xmlns", "bk", Nothing, "urn:samples")
writer.WriteStartElement("book")
'Lookup the prefix and then write the ISBN attribute.
Dim prefix As String = writer.LookupPrefix("urn:samples")
writer.WriteStartAttribute(prefix, "ISBN", "urn:samples")
writer.WriteString("1-861003-78")
writer.WriteEndAttribute()
'Write the title.
writer.WriteStartElement("title")
writer.WriteString("The Handmaid's Tale")
writer.WriteEndElement()
'Write the price.
writer.WriteElementString("price", "19.95")
'Write the style element.
writer.WriteStartElement(prefix, "style", "urn:samples")
writer.WriteString("hardcover")
writer.WriteEndElement()
'Write the end tag for the book element.
writer.WriteEndElement()
'Write the close tag for the root element.
writer.WriteEndElement()
'Write the XML to file and close the writer.
writer.Flush()
writer.Close()
'Read the file back in and parse to ensure well formed XML.
Dim doc As New XmlDocument()
'Preserve white space for readability.
doc.PreserveWhitespace = True
'Load the file.
doc.Load(filename)
'Write the XML content to the console.
Console.Write(doc.InnerXml)
End Sub
End Class
Комментарии
Примечание
Начиная с версии платформа .NET Framework 2.0 рекомендуется создавать XmlWriter экземпляры с помощью XmlWriter.Create метода и XmlWriterSettings класса, чтобы воспользоваться преимуществами новых функциональных возможностей.
После вызова этого метода можно либо написать атрибуты, либо создать содержимое с помощью WriteComment, WriteStringлибо WriteStartElement для дочерних элементов. Элемент можно закрыть, с WriteEndElement помощью которого выписывается конечный тег.