XmlWriter.LookupPrefix(String) XmlWriter.LookupPrefix(String) XmlWriter.LookupPrefix(String) XmlWriter.LookupPrefix(String) Method

정의

파생 클래스에서 재정의되면 네임스페이스 URI의 현재 네임스페이스 범위에 정의된 가장 비슷한 접두사를 반환합니다.When overridden in a derived class, returns the closest prefix defined in the current namespace scope for the namespace URI.

public:
 abstract System::String ^ LookupPrefix(System::String ^ ns);
public abstract string LookupPrefix (string ns);
abstract member LookupPrefix : string -> string
Public MustOverride Function LookupPrefix (ns As String) As String

매개 변수

ns
String String String String

찾으려는 접두사를 가진 네임스페이스 URI입니다.The namespace URI whose prefix you want to find.

반환

일치하는 접두사이거나 현재 범위에 일치하는 네임스페이스 URI가 없는 경우 null입니다.The matching prefix or null if no matching namespace URI is found in the current scope.

예외

nsnull 또는 String.Empty입니다.ns is either null or String.Empty.

이전 비동기 작업이 완료되기 전에 XmlWriter 메서드가 호출되었습니다.An XmlWriter method was called before a previous asynchronous operation finished. 이 경우 “비동기 작업이 이미 진행 중입니다.” 메시지를 나타내며 InvalidOperationException이 throw됩니다.In this case, InvalidOperationException is thrown with the message "An asynchronous operation is already in progress."

예제

다음 예제에서는 책을 작성 합니다.The following example writes out a book.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
public ref class Sample
{
private:
   static String^ m_Document = L"sampledata.xml";

public:
   static void Main()
   {
      XmlWriter^ writer = nullptr;
      try
      {
         XmlWriterSettings^ settings = gcnew XmlWriterSettings;
         settings->Indent = true;
         writer = XmlWriter::Create( m_Document,settings );
         writer->WriteComment( L"sample XML fragment" );
         
         // Write an element (this one is the root).
         writer->WriteStartElement( L"book" );
         
         // Write the namespace declaration.
         writer->WriteAttributeString( L"xmlns", L"bk", nullptr, L"urn:samples" );
         
         // Write the genre attribute.
         writer->WriteAttributeString( L"genre", L"novel" );
         
         // Write the title.
         writer->WriteStartElement( L"title" );
         writer->WriteString( L"The Handmaid's Tale" );
         writer->WriteEndElement();
         
         // Write the price.
         writer->WriteElementString( L"price", L"19.95" );
         
         // Lookup the prefix and write the ISBN element.
         String^ prefix = writer->LookupPrefix( L"urn:samples" );
         writer->WriteStartElement( prefix, L"ISBN", L"urn:samples" );
         writer->WriteString( L"1-861003-78" );
         writer->WriteEndElement();
         
         // Write the style element (shows a different way to handle prefixes).
         writer->WriteElementString( L"style", L"urn:samples", L"hardcover" );
         
         // Write the close tag for the root element.
         writer->WriteEndElement();
         
         // Write the XML to file and close the writer.
         writer->Flush();
         writer->Close();
      }
      finally
      {
         if ( writer != nullptr )
                  writer->Close();
      }

   }

};

void main()
{
   Sample::Main();
}

using System;
using System.IO;
using System.Xml;
 
 public class Sample
 {
   private const string m_Document = "sampledata.xml";
 
   public static void Main() {
   
      XmlWriter writer = null;

      try {
     
        XmlWriterSettings settings = new XmlWriterSettings();
        settings.Indent = true;
        writer = XmlWriter.Create (m_Document, settings);
           
        writer.WriteComment("sample XML fragment");
     
        // Write an element (this one is the root).
        writer.WriteStartElement("book");
 
        // Write the namespace declaration.
        writer.WriteAttributeString("xmlns", "bk", null, "urn:samples");
    
        // Write the genre attribute.
        writer.WriteAttributeString("genre", "novel");
         
        // Write the title.
        writer.WriteStartElement("title");
        writer.WriteString("The Handmaid's Tale");
        writer.WriteEndElement();
               
        // Write the price.
        writer.WriteElementString("price", "19.95");
      
        // Lookup the prefix and write the ISBN element.
        string prefix = writer.LookupPrefix("urn:samples");
        writer.WriteStartElement(prefix, "ISBN", "urn:samples");
        writer.WriteString("1-861003-78");
        writer.WriteEndElement();

        // Write the style element (shows a different way to handle prefixes).
        writer.WriteElementString("style", "urn:samples", "hardcover");
 
        // Write the close tag for the root element.
        writer.WriteEndElement();
               
        // Write the XML to file and close the writer.
        writer.Flush();
        writer.Close();
      }

      finally {
        if (writer != null)
           writer.Close();
     } 
   }
 
 }
Option Strict
Option Explicit

Imports System
Imports System.IO
Imports System.Xml

Public Class Sample
    Private Shared m_Document As String = "sampledata.xml"
    
    Public Shared Sub Main()
        Dim writer As XmlWriter = Nothing
        
      Try

        Dim settings As XmlWriterSettings = new XmlWriterSettings()
        settings.Indent = true
        writer = XmlWriter.Create (m_Document, settings)
            
        writer.WriteComment("sample XML fragment")
            
        ' Write an element (this one is the root).
        writer.WriteStartElement("book")
            
        ' Write the namespace declaration.
        writer.WriteAttributeString("xmlns", "bk", Nothing, "urn:samples")
            
        ' Write the genre attribute.
        writer.WriteAttributeString("genre", "novel")
            
        ' Write the title.
        writer.WriteStartElement("title")
        writer.WriteString("The Handmaid's Tale")
        writer.WriteEndElement()
            
        ' Write the price.
        writer.WriteElementString("price", "19.95")
            
        ' Lookup the prefix and write the ISBN element.
        Dim prefix As String = writer.LookupPrefix("urn:samples")
        writer.WriteStartElement(prefix, "ISBN", "urn:samples")
        writer.WriteString("1-861003-78")
        writer.WriteEndElement()
            
        ' Write the style element (shows a different way to handle prefixes).
        writer.WriteElementString("style", "urn:samples", "hardcover")
            
        ' Write the close tag for the root element.
        writer.WriteEndElement()
            
        ' Write the XML to file and close the writer.
        writer.Flush()
        writer.Close()
        
        Finally
            If Not (writer Is Nothing) Then
                writer.Close()
            End If
        End Try

    End Sub 'Main 
End Class 'Sample

적용 대상