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XmlValidatingReader.Read Methode

Definition

Liest den nächsten Knoten aus dem Stream.

public:
 override bool Read();
public override bool Read ();
override this.Read : unit -> bool
Public Overrides Function Read () As Boolean

Gibt zurück

true, wenn der nächste Knoten erfolgreich gelesen wurde, false, wenn keine weiteren zu lesenden Knoten vorhanden sind.

Beispiele

Im folgenden Beispiel wird eine XML-Datei gelesen und jeder Knoten angezeigt.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
   XmlTextReader^ txtreader = nullptr;
   XmlValidatingReader^ reader = nullptr;
   String^ filename = "items.xml";
   try
   {
      
      //Load the reader with the data file and ignore all white space nodes.         
      txtreader = gcnew XmlTextReader( filename );
      txtreader->WhitespaceHandling = WhitespaceHandling::None;
      
      //Implement the validating reader over the text reader. 
      reader = gcnew XmlValidatingReader( txtreader );
      reader->ValidationType = ValidationType::None;
      
      //Parse the file and display each of the nodes.
      while ( reader->Read() )
      {
         switch ( reader->NodeType )
         {
            case XmlNodeType::Element:
               Console::Write( "<{0}>", reader->Name );
               break;

            case XmlNodeType::Text:
               Console::Write( reader->Value );
               break;

            case XmlNodeType::CDATA:
               Console::Write( "<![CDATA[{0}]]>", reader->Value );
               break;

            case XmlNodeType::ProcessingInstruction:
               Console::Write( "<?{0} {1}?>", reader->Name, reader->Value );
               break;

            case XmlNodeType::Comment:
               Console::Write( "<!--{0}-->", reader->Value );
               break;

            case XmlNodeType::XmlDeclaration:
               Console::Write( "<?xml version='1.0'?>" );
               break;

            case XmlNodeType::Document:
               break;

            case XmlNodeType::DocumentType:
               Console::Write( "<!DOCTYPE {0} [{1}]", reader->Name, reader->Value );
               break;

            case XmlNodeType::EntityReference:
               Console::Write( reader->Name );
               break;

            case XmlNodeType::EndElement:
               Console::Write( "</{0}>", reader->Name );
               break;
         }
      }
   }
   finally
   {
      if ( reader != nullptr )
            reader->Close();
   }

}

using System;
using System.IO;
using System.Xml;

public class Sample
{
  private const String filename = "items.xml";

  public static void Main()
  {
     XmlTextReader txtreader = null;
     XmlValidatingReader reader = null;

     try
     {
        //Load the reader with the data file and ignore all white space nodes.
        txtreader = new XmlTextReader(filename);
        txtreader.WhitespaceHandling = WhitespaceHandling.None;

        //Implement the validating reader over the text reader.
        reader = new XmlValidatingReader(txtreader);
        reader.ValidationType = ValidationType.None;

        //Parse the file and display each of the nodes.
        while (reader.Read())
        {
           switch (reader.NodeType)
           {
             case XmlNodeType.Element:
               Console.Write("<{0}>", reader.Name);
               break;
             case XmlNodeType.Text:
               Console.Write(reader.Value);
               break;
             case XmlNodeType.CDATA:
               Console.Write("<![CDATA[{0}]]>", reader.Value);
               break;
             case XmlNodeType.ProcessingInstruction:
               Console.Write("<?{0} {1}?>", reader.Name, reader.Value);
               break;
             case XmlNodeType.Comment:
               Console.Write("<!--{0}-->", reader.Value);
               break;
             case XmlNodeType.XmlDeclaration:
               Console.Write("<?xml version='1.0'?>");
               break;
             case XmlNodeType.Document:
               break;
             case XmlNodeType.DocumentType:
               Console.Write("<!DOCTYPE {0} [{1}]", reader.Name, reader.Value);
               break;
             case XmlNodeType.EntityReference:
               Console.Write(reader.Name);
               break;
             case XmlNodeType.EndElement:
               Console.Write("</{0}>", reader.Name);
               break;
           }
        }
     }

     finally
     {
        if (reader!=null)
          reader.Close();
     }
  }
} // End class
Imports System.IO
Imports System.Xml

Public Class Sample
   Private Const filename As String = "items.xml"
   
   Public Shared Sub Main()
      Dim txtreader As XmlTextReader = Nothing
      Dim reader As XmlValidatingReader = Nothing
      
      Try
         'Load the reader with the data file and ignore all white space nodes.         
         txtreader = New XmlTextReader(filename)
         txtreader.WhitespaceHandling = WhitespaceHandling.None
         
         'Implement the validating reader over the text reader. 
         reader = New XmlValidatingReader(txtreader)
         reader.ValidationType = ValidationType.None
         
         'Parse the file and display each of the nodes.
         While reader.Read()
            Select Case reader.NodeType
               Case XmlNodeType.Element
                  Console.Write("<{0}>", reader.Name)
               Case XmlNodeType.Text
                  Console.Write(reader.Value)
               Case XmlNodeType.CDATA
                  Console.Write("<![CDATA[{0}]]>", reader.Value)
               Case XmlNodeType.ProcessingInstruction
                  Console.Write("<?{0} {1}?>", reader.Name, reader.Value)
               Case XmlNodeType.Comment
                  Console.Write("<!--{0}-->", reader.Value)
               Case XmlNodeType.XmlDeclaration
                  Console.Write("<?xml version='1.0'?>")
               Case XmlNodeType.Document
               Case XmlNodeType.DocumentType
                  Console.Write("<!DOCTYPE {0} [{1}]", reader.Name, reader.Value)
               Case XmlNodeType.EntityReference
                  Console.Write(reader.Name)
               Case XmlNodeType.EndElement
                  Console.Write("</{0}>", reader.Name)
            End Select
         End While
      
      Finally
         If Not (reader Is Nothing) Then
            reader.Close()
         End If
      End Try
   End Sub
End Class

Im Beispiel wird die Datei als items.xmlEingabe verwendet.


<?xml version="1.0"?>
<!-- This is a sample XML document -->
<!DOCTYPE Items [<!ENTITY number "123">]>
<Items>
  <Item>Test with an entity: &number;</Item>
  <Item>test with a child element <more/> stuff</Item>
  <Item>test with a CDATA section <![CDATA[<456>]]> def</Item>
  <Item>Test with a char entity: &#65;</Item>
  <!-- Fourteen chars in this element.-->
  <Item>1234567890ABCD</Item>
</Items>

Hinweise

Hinweis

Die XmlValidatingReader Klasse ist in .NET Framework 2.0 veraltet. Sie können eine Validierungsinstanz XmlReader erstellen, indem Sie die XmlReaderSettings -Klasse und die Create -Methode verwenden. Weitere Informationen finden Sie im Abschnitt Hinweise unter der XmlReader Referenzseite.

Wenn ein Leser zum ersten Mal erstellt und initialisiert wird, sind keine Informationen verfügbar. Sie müssen aufrufen Read , um den ersten Knoten zu lesen.

Gilt für:

Weitere Informationen