XmlTextWriter.WriteProcessingInstruction(String, String) 方法

定义

写出在名称和文本之间有空格的处理指令,如下所示:<?name text?>。

public:
 override void WriteProcessingInstruction(System::String ^ name, System::String ^ text);
public override void WriteProcessingInstruction (string name, string? text);
public override void WriteProcessingInstruction (string name, string text);
override this.WriteProcessingInstruction : string * string -> unit
Public Overrides Sub WriteProcessingInstruction (name As String, text As String)

参数

name
String

处理指令的名称。

text
String

要包括在处理指令中的文本。

例外

该文本将导致格式不正确的 XML 文档。

namenullString.Empty

调用了 WriteStartDocument() 后,使用此方法创建 XML 声明。

示例

以下示例编写一个表示书籍的 XML 文件。

#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

注解

备注

从 .NET Framework 2.0 开始,我们建议使用XmlWriter.Create方法和XmlWriterSettings类创建XmlWriter实例,以利用新功能。

如果text为任一方法String.Emptynull则此方法写入ProcessingInstruction没有数据内容,例如<?name?>。

适用于