XmlTextWriter.WriteDocType(String, String, String, String) Método

Definición

Espacio de nombres:

System.Xml

Ensamblado:

System.Xml.dll

Escribe la declaración DOCTYPE con el nombre especificado y los atributos opcionales.

public:
 override void WriteDocType(System::String ^ name, System::String ^ pubid, System::String ^ sysid, System::String ^ subset);

public override void WriteDocType(string name, string pubid, string sysid, string subset);

override this.WriteDocType : string * string * string * string -> unit

Public Overrides Sub WriteDocType (name As String, pubid As String, sysid As String, subset As String)

Parámetros

name

String

Nombre del DOCTYPE. Debe no estar vacío.

pubid

String

Si no es null, también escribe PUBLIC "pubid" "sysid" donde pubid y sysid se reemplazan por el valor de los argumentos especificados.

sysid

String

Si pubid es null y sysid no es NULL, escribe SYSTEM "sysid" donde sysid se reemplaza por el valor de este argumento.

subset

String

Si no es null, escribe [subconjunto] donde el subconjunto se reemplaza por el valor de este argumento.

Excepciones

InvalidOperationException

Este método se llamó fuera del prólogo (después del elemento raíz).

ArgumentException

name es null o String.Empty

O bien

el valor de name daría como resultado XML no válido.

Ejemplos

En el ejemplo siguiente se escribe un archivo XML que representa un libro.

using System;
using System.IO;
using System.Xml;

public class Sample
{
  private const string filename = "sampledata.xml";

  public static void Main()
  {
     XmlTextWriter writer = null;

     writer = new XmlTextWriter (filename, null);
     //Use indenting for readability.
     writer.Formatting = Formatting.Indented;

     //Write the XML delcaration.
     writer.WriteStartDocument();

     //Write the ProcessingInstruction node.
     String PItext="type='text/xsl' href='book.xsl'";
     writer.WriteProcessingInstruction("xml-stylesheet", PItext);

     //Write the DocumentType node.
     writer.WriteDocType("book", null , null, "<!ENTITY h 'hardcover'>");

     //Write a Comment node.
     writer.WriteComment("sample XML");

     //Write a root element.
     writer.WriteStartElement("book");

     //Write the genre attribute.
     writer.WriteAttributeString("genre", "novel");

     //Write the ISBN attribute.
     writer.WriteAttributeString("ISBN", "1-8630-014");

     //Write the title.
     writer.WriteElementString("title", "The Handmaid's Tale");

     //Write the style element.
     writer.WriteStartElement("style");
     writer.WriteEntityRef("h");
     writer.WriteEndElement();

     //Write the price.
     writer.WriteElementString("price", "19.95");

     //Write CDATA.
     writer.WriteCData("Prices 15% off!!");

     //Write the close tag for the root element.
     writer.WriteEndElement();

     writer.WriteEndDocument();

     //Write the XML to file and close the writer.
     writer.Flush();
     writer.Close();

     //Load the file into an XmlDocument to ensure well formed XML.
     XmlDocument doc = new XmlDocument();
     //Preserve white space for readability.
     doc.PreserveWhitespace = true;
     //Load the file.
     doc.Load(filename);

     //Display the XML content to the console.
     Console.Write(doc.InnerXml);
  }
}

Option Explicit
Option Strict

Imports System.IO
Imports System.Xml

Public Class Sample
    Private Shared filename As String = "sampledata.xml"
    Public Shared Sub Main()
        Dim writer As XmlTextWriter = Nothing
        
        writer = New XmlTextWriter(filename, Nothing)
        'Use indenting for readability.
        writer.Formatting = Formatting.Indented
        
        'Write the XML delcaration. 
        writer.WriteStartDocument()
        
        'Write the ProcessingInstruction node.
        Dim PItext As String = "type='text/xsl' href='book.xsl'"
        writer.WriteProcessingInstruction("xml-stylesheet", PItext)
        
        'Write the DocumentType node.
        writer.WriteDocType("book", Nothing, Nothing, "<!ENTITY h 'hardcover'>")
        
        'Write a Comment node.
        writer.WriteComment("sample XML")
        
        'Write a root element.
        writer.WriteStartElement("book")
        
        'Write the genre attribute.
        writer.WriteAttributeString("genre", "novel")
        
        'Write the ISBN attribute.
        writer.WriteAttributeString("ISBN", "1-8630-014")
        
        'Write the title.
        writer.WriteElementString("title", "The Handmaid's Tale")
        
        'Write the style element.
        writer.WriteStartElement("style")
        writer.WriteEntityRef("h")
        writer.WriteEndElement()
        
        'Write the price.
        writer.WriteElementString("price", "19.95")
        
        'Write CDATA.
        writer.WriteCData("Prices 15% off!!")
        
        'Write the close tag for the root element.
        writer.WriteEndElement()
        
        writer.WriteEndDocument()
        
        'Write the XML to file and close the writer.
        writer.Flush()
        writer.Close()
        
        'Load the file into an XmlDocument to ensure well formed XML.
        Dim doc As New XmlDocument()
        'Preserve white space for readability.
        doc.PreserveWhitespace = True
        'Load the file.
        doc.Load(filename)
        
        'Display the XML content to the console.
        Console.Write(doc.InnerXml)
    End Sub
End Class

Comentarios

Note

Se recomienda crear XmlWriter instancias mediante el XmlWriter.Create método y la XmlWriterSettings clase para aprovechar las nuevas funcionalidades.

Este método no comprueba si hay caracteres no válidos en pubido sysidsubset. Tampoco comprueba que el subconjunto interno esté bien formado.

Importante

XmlTextWriter no valida ningún dato que se pase al WriteDocType método . No debe pasar datos arbitrarios a este método.