XmlWriter.WriteComment(String) Method

Definition

在衍生類別中覆寫時,寫出包含指定文字的註解 <!--...-->。When overridden in a derived class, writes out a comment <!--...--> containing the specified text.

public:
 abstract void WriteComment(System::String ^ text);
public abstract void WriteComment (string text);
abstract member WriteComment : string -> unit
Public MustOverride Sub WriteComment (text As String)

Parameters

text
String

要放入註解中的文字。Text to place inside the comment.

Exceptions

此文字會導致非語式正確的 XML 文件。The text would result in a non-well-formed XML document.

在先前的非同步作業完成前呼叫了 XmlWriter 方法。An XmlWriter method was called before a previous asynchronous operation finished. 在此情況下,會擲回 InvalidOperationException 與「非同步作業已經在進行中」的訊息。In this case, InvalidOperationException is thrown with the message "An asynchronous operation is already in progress."

Examples

下列範例會寫入代表書籍的 XML 檔案。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() {

     XmlWriterSettings settings = new XmlWriterSettings();
     settings.Indent = true;
     XmlWriter writer = XmlWriter.Create(filename, settings);

     // Write the Processing Instruction 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 the 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();
  }
}
Option Strict
Option Explicit

Imports System.IO
Imports System.Xml

Public Class Sample
    Private Const filename As String = "sampledata.xml"
    
  Public Shared Sub Main()

     Dim settings As XmlWriterSettings = new XmlWriterSettings()
     settings.Indent = true
     Dim writer As XmlWriter = XmlWriter.Create(filename, settings)
        
     ' Write the Processing Instruction 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 the 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()
        
    End Sub
End Class

Remarks

如果 textnullString.Empty,則此方法會寫入沒有資料內容的批註,例如 <!---->。If text is either null or String.Empty, this method writes a comment with no data content, for example <!---->.

如果 text 包含兩個虛線的無效序列 "--",XmlWriter 可以擲回 ArgumentExceptionXmlTextWriter 物件),或在破折號 "--" 之間插入空格,讓文字是有效的 XML 批註(XmlWriter 方法所建立的 Create 物件)。If text contains an invalid sequence of two dashes "--" the XmlWriter can either throw an ArgumentException (XmlTextWriter objects) or insert a space between the dashes "- -" so that the text is a valid XML comment (XmlWriter objects created by the Create method).

如需這個方法的非同步版本,請參閱 WriteCommentAsyncFor the asynchronous version of this method, see WriteCommentAsync.

Applies to