XmlTextReader.WhitespaceHandling Proprietà

Definizione

Ottiene o imposta un valore che specifica come viene gestito lo spazio vuoto.Gets or sets a value that specifies how white space is handled.

public:
 property System::Xml::WhitespaceHandling WhitespaceHandling { System::Xml::WhitespaceHandling get(); void set(System::Xml::WhitespaceHandling value); };
public System.Xml.WhitespaceHandling WhitespaceHandling { get; set; }
member this.WhitespaceHandling : System.Xml.WhitespaceHandling with get, set
Public Property WhitespaceHandling As WhitespaceHandling

Valore della proprietà

Uno dei valori di WhitespaceHandling.One of the WhitespaceHandling values. Il valore predefinito è WhitespaceHandling.All (restituisce i nodi Whitespace e SignificantWhitespace).The default is WhitespaceHandling.All (returns Whitespace and SignificantWhitespace nodes).

Eccezioni

È stato specificato un valore non valido.Invalid value specified.

Impostare questa proprietà quando il visualizzatore è chiuso (ReadState è ReadState.Closed).Setting this property when the reader is closed (ReadState is ReadState.Closed).

Esempi

Nell'esempio seguente viene letto un frammento XML.The following example reads an XML fragment.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
void ReadXML( XmlParserContext^ context, String^ xmlFrag, WhitespaceHandling ws )
{
   
   //Create the reader and specify the WhitespaceHandling setting.
   XmlTextReader^ reader = gcnew XmlTextReader( xmlFrag,XmlNodeType::Element,context );
   reader->WhitespaceHandling = ws;
   
   //Parse the XML and display each of the nodes.
   while ( reader->Read() )
   {
      switch ( reader->NodeType )
      {
         case XmlNodeType::Element:
            Console::WriteLine( "{0}: <{1}>", reader->NodeType, reader->Name );
            break;

         case XmlNodeType::Text:
            Console::WriteLine( "{0}: {1}", reader->NodeType, reader->Value );
            break;

         case XmlNodeType::EndElement:
            Console::WriteLine( "{0}: </{1}>", reader->NodeType, reader->Name );
            break;

         case XmlNodeType::Whitespace:
            Console::WriteLine( "{0}:", reader->NodeType );
            break;

         case XmlNodeType::SignificantWhitespace:
            Console::WriteLine( "{0}:", reader->NodeType );
            break;
      }
   }

   
   //Close the reader.
   reader->Close();
}

int main()
{
   
   //Create the XML fragment to be parsed.
   String^ xmlFrag = "<book> "
   "  <title>Pride And Prejudice</title>"
   "  <genre>novel</genre>"
   "</book>";
   
   //Create the XmlNamespaceManager.
   NameTable^ nt = gcnew NameTable;
   XmlNamespaceManager^ nsmgr = gcnew XmlNamespaceManager( nt );
   
   //Create the XmlParserContext.
   XmlParserContext^ context = gcnew XmlParserContext( nullptr,nsmgr,nullptr,XmlSpace::Default );
   Console::WriteLine( "Read the XML and ignore all white space..." );
   ReadXML( context, xmlFrag, WhitespaceHandling::None );
   Console::WriteLine( "\r\nRead the XML including white space nodes..." );
   ReadXML( context, xmlFrag, WhitespaceHandling::All );
}

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

public class Sample 
{
  public static void Main(){

    //Create the XML fragment to be parsed.
    string xmlFrag ="<book> " +
                    "  <title>Pride And Prejudice</title>" +
                    "  <genre>novel</genre>" +
                    "</book>"; 

    //Create the XmlNamespaceManager.
    NameTable nt = new NameTable();
    XmlNamespaceManager nsmgr = new XmlNamespaceManager(nt);

    //Create the XmlParserContext.
    XmlParserContext context = new XmlParserContext(null, nsmgr, null, XmlSpace.Default);

    Console.WriteLine("Read the XML and ignore all white space...");
    ReadXML(context, xmlFrag, WhitespaceHandling.None);

    Console.WriteLine("\r\nRead the XML including white space nodes...");
    ReadXML(context, xmlFrag, WhitespaceHandling.All);
  }
  
  public static void ReadXML(XmlParserContext context, string xmlFrag, WhitespaceHandling ws){

    //Create the reader and specify the WhitespaceHandling setting.
    XmlTextReader reader = new XmlTextReader(xmlFrag, XmlNodeType.Element, context);
    reader.WhitespaceHandling = ws;

      //Parse the XML and display each of the nodes.
      while (reader.Read())
      {
         switch (reader.NodeType)
         {
           case XmlNodeType.Element:
             Console.WriteLine("{0}: <{1}>", reader.NodeType, reader.Name);
             break;
           case XmlNodeType.Text:
             Console.WriteLine("{0}: {1}", reader.NodeType, reader.Value);
             break;
           case XmlNodeType.EndElement:
             Console.WriteLine("{0}: </{1}>", reader.NodeType, reader.Name);
             break;
           case XmlNodeType.Whitespace:
             Console.WriteLine("{0}:", reader.NodeType);
             break;
           case XmlNodeType.SignificantWhitespace:
             Console.WriteLine("{0}:", reader.NodeType);
             break;
         }       
      }           
  
    //Close the reader.
    reader.Close();     
  }
} // End class

Imports System.IO
Imports System.Xml

public class Sample 

  public shared sub Main()

    'Create the XML fragment to be parsed.
    Dim xmlFrag as string ="<book> " & _
                           "  <title>Pride And Prejudice</title>" & _
                           "  <genre>novel</genre>" & _
                           "</book>" 

    'Create the XmlNamespaceManager.
    Dim nt as NameTable = new NameTable()
    Dim nsmgr as XmlNamespaceManager = new XmlNamespaceManager(nt)

    'Create the XmlParserContext.
    Dim context as XmlParserContext = new XmlParserContext(nothing, nsmgr, nothing, XmlSpace.Default)

    Console.WriteLine("Read the XML and ignore all white space...")
    ReadXML(context, xmlFrag, WhitespaceHandling.None)

    Console.WriteLine()
    Console.WriteLine("Read the XML including white space nodes...")
    ReadXML(context, xmlFrag, WhitespaceHandling.All)
  end sub
  
  public shared sub ReadXML(context as XmlParserContext, xmlFrag as string, ws as WhitespaceHandling)

    'Create the reader and specify the WhitespaceHandling setting.
    Dim reader as XmlTextReader = new XmlTextReader(xmlFrag, XmlNodeType.Element, context)
    reader.WhitespaceHandling = ws

      'Parse the XML and display each of the nodes.
      while (reader.Read())
         select case reader.NodeType
           case XmlNodeType.Element:
             Console.WriteLine("{0}: <{1}>", reader.NodeType, reader.Name)
           case XmlNodeType.Text:
             Console.WriteLine("{0}: {1}", reader.NodeType, reader.Value)
           case XmlNodeType.EndElement:
             Console.WriteLine("{0}: </{1}>", reader.NodeType, reader.Name)
           case XmlNodeType.Whitespace:
             Console.WriteLine("{0}:", reader.NodeType)
           case XmlNodeType.SignificantWhitespace:
             Console.WriteLine("{0}:", reader.NodeType)
         end select       
      end while           
  
    'Close the reader.
    reader.Close()     
  
  end sub
end class

Commenti

Nota

A partire dalla .NET Framework 2,0, è consigliabile creare istanze di XmlReader usando il metodo XmlReader.Create per sfruttare le nuove funzionalità.Starting with the .NET Framework 2.0, we recommend that you create XmlReader instances by using the XmlReader.Create method to take advantage of new functionality.

Questa proprietà può essere modificata in qualsiasi momento e diventa effettiva alla successiva operazione di lettura.This property can be changed at any time and takes effect on the next read operation.

Poiché il XmlTextReader non dispone di informazioni DTD, i nodi SignificantWhitepsace vengono restituiti solo in un ambito di xml:space='preserve'.Because the XmlTextReader does not have DTD information available to it, SignificantWhitepsace nodes are only returned within an xml:space='preserve' scope.

Si applica a

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