Export (0) Print
Expand All

XmlTextWriter.WriteDocType Method

Writes the DOCTYPE declaration with the specified name and optional attributes.

Namespace:  System.Xml
Assembly:  System.Xml (in System.Xml.dll)

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


Type: System.String

The name of the DOCTYPE. This must be non-empty.

Type: System.String

If non-null it also writes PUBLIC "pubid" "sysid" where pubid and sysid are replaced with the value of the given arguments.

Type: System.String

If pubid is null and sysid is non-null it writes SYSTEM "sysid" where sysid is replaced with the value of this argument.

Type: System.String

If non-null it writes [subset] where subset is replaced with the value of this argument.


This method was called outside the prolog (after the root element).


name is null or String.Empty


the value for name would result in invalid XML.


Starting with the .NET Framework 2.0, we recommend that you create XmlWriter instances by using the XmlWriter.Create method and the XmlWriterSettings class to take advantage of new functionality.

This method does not check for invalid characters in pubid, sysid or subset. It also does not check that the internal subset is well-formed.

Security noteSecurity Note

The XmlTextWriter does not validate any data that is passed to the WriteDocType method. You should not pass arbitrary data to this method.

The following example writes an XML file representing a book.

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. 

     //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.

     //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.

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

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

     //Write the close tag for the root element.


     //Write the XML to file and close the writer.

     //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.

     //Display the XML content to the console.



.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

© 2014 Microsoft