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XmlTextWriter.WriteStartDocument Method

  • Reference

Definition

Namespace:
System.Xml
Assembly:
System.Xml.ReaderWriter.dll
Assembly:
System.Xml.dll
Assembly:
netstandard.dll

Writes the XML declaration with the version "1.0".

Overloads

WriteStartDocument()

Writes the XML declaration with the version "1.0".
WriteStartDocument(Boolean)

Writes the XML declaration with the version "1.0" and the standalone attribute.

Remarks

Note

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.

WriteStartDocument()

Source:
XmlTextWriter.cs
Source:
XmlTextWriter.cs
Source:
XmlTextWriter.cs

Writes the XML declaration with the version "1.0".

public:
 override void WriteStartDocument();
public override void WriteStartDocument ();
override this.WriteStartDocument : unit -> unit
Public Overrides Sub WriteStartDocument ()

Exceptions

InvalidOperationException

This is not the first write method called after the constructor.

Examples

The following example writes an XML file representing a book.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
   XmlTextWriter^ writer = nullptr;
   String^ filename = "sampledata.xml";
   writer = gcnew XmlTextWriter( filename, nullptr );
   
   //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", nullptr, nullptr, "<!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 = gcnew 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 );
}

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

Remarks

Note

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.

The encoding level of the document is determined by how the writer is implemented. For example, if an Encoding object is specified in the XmlTextWriter constructor, this determines the value of the encoding attribute. This method does not create a standalone attribute.

When WriteStartDocument is called the writer validates that what you are writing is a well-formed XML document. For example, it checks that the XML declaration is the first node, that one and only one root-level element exists and so on. If this method is not called, the writer assumes an XML fragment is being written and applies no root level rules.

If WriteStartDocument has been called and then the WriteProcessingInstruction method is used to create another XML declaration, an exception is thrown.

Applies to

WriteStartDocument(Boolean)

Source:
XmlTextWriter.cs
Source:
XmlTextWriter.cs
Source:
XmlTextWriter.cs

Writes the XML declaration with the version "1.0" and the standalone attribute.

public:
 override void WriteStartDocument(bool standalone);
public override void WriteStartDocument (bool standalone);
override this.WriteStartDocument : bool -> unit
Public Overrides Sub WriteStartDocument (standalone As Boolean)

Parameters

standalone
Boolean

If true, it writes "standalone=yes"; if false, it writes "standalone=no".

Exceptions

InvalidOperationException

This is not the first write method called after the constructor.

Remarks

Note

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.

The encoding level of the document is determined by how the writer is implemented. For example, if an Encoding object is specified in the XmlTextWriter constructor, this determines the value of the encoding attribute.

When WriteStartDocument is called the writer validates that what you are writing is a well-formed XML document. For example, it checks that the XML declaration is the first node, that one and only one root-level element exists and so on. If this method is not called, the writer assumes an XML fragment is being written and applies no root level rules.

If WriteStartDocument has been called and then the WriteProcessingInstruction method is used to create another XML declaration, an exception is thrown.

Applies to