XmlTextWriter.WriteStartElement(String, String, String) Método
Definição
Importante
Algumas informações dizem respeito a um produto pré-lançado que pode ser substancialmente modificado antes de ser lançado. A Microsoft não faz garantias, de forma expressa ou implícita, em relação à informação aqui apresentada.
Escreve a etiqueta inicial especificada e associa-a ao namespace e prefixo atribuídos.
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)
Parâmetros
- prefix
- String
O prefixo de namespace do elemento.
- localName
- String
O nome local do elemento.
- ns
- String
O URI do namespace para associar ao elemento. Se este namespace já estiver no âmbito e tiver um prefixo associado, então o autor escreve automaticamente esse prefixo também.
Exceções
O escritor está fechado.
Exemplos
O exemplo seguinte escreve um livro.
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
Observações
Note
Recomendamos que crie instâncias XmlWriter usando o método XmlWriter.Create e a classe XmlWriterSettings para aproveitar a nova funcionalidade.
Depois de chamar este método, pode escrever atributos ou criar conteúdo usando WriteComment, WriteString, ou WriteStartElement para elementos filhos. Pode fechar o elemento com WriteEndElement o momento em que a tag final é escrita.