XmlTextReader.WhitespaceHandling Vlastnost

Definice

Obor názvů:

System.Xml

Sestavení:

System.Xml.ReaderWriter.dll

Source:

XmlTextReader.cs

Získá nebo nastaví hodnotu, která určuje způsob zpracování prázdných znaků.

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

Hodnota vlastnosti

WhitespaceHandling

Jedna z WhitespaceHandling hodnot. Výchozí hodnota je WhitespaceHandling.All (vrátí Whitespace a SignificantWhitespace uzly).

Výjimky

ArgumentOutOfRangeException

Byla zadána neplatná hodnota.

InvalidOperationException

Nastavení této vlastnosti při zavření čtečky (ReadState je ReadState.Closed).

Příklady

Následující příklad čte fragment XML.

#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

Poznámky

Poznámka

Počínaje rozhraním .NET Framework 2.0 doporučujeme vytvářet XmlReader instance pomocí XmlReader.Create metody, abyste mohli využívat nové funkce.

Tuto vlastnost lze kdykoli změnit a projeví se při další operaci čtení.

Vzhledem k tomu, že XmlTextReader objekt nemá k dispozici informace DTD, SignificantWhitespace jsou uzly vráceny pouze v rámci xml:space='preserve' oboru.

Viz také

• XmlReader