XmlNodeReader.Value 屬性

定義

命名空間:

System.Xml

組件:

System.Xml.ReaderWriter.dll

組件:

System.Xml.dll

組件:

netstandard.dll

取得目前節點的文字值。

public:
 virtual property System::String ^ Value { System::String ^ get(); };

public override string Value { get; }

member this.Value : string

Public Overrides ReadOnly Property Value As String

屬性值

String

傳回值需視節點的 NodeType 而定。 下表列出具有傳回值的節點類型。 其他所有節點類型都會傳回 String.Empty。

節點類型	值
Attribute	屬性的值。
CDATA	CDATA 區段的內容。
Comment	註解的內容。
DocumentType	內部子集。
ProcessingInstruction	全部內容 (目標除外)。
SignificantWhitespace	在混合內容模型中標記間的泛空白字元。
Text	文字節點的內容。
Whitespace	標記之間的泛空白字元。
XmlDeclaration	宣告的內容。

範例

下列範例會讀取 XML 並顯示每個節點。

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
   String^ filename = "items.xml";
   XmlNodeReader^ reader = nullptr;
   try
   {
      
      //Create an XmlNodeReader to read the XmlDocument.
      XmlDocument^ doc = gcnew XmlDocument;
      doc->Load( filename );
      reader = gcnew XmlNodeReader( doc );
      
      //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( 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::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()
  {
    XmlNodeReader reader = null;

    try
    {
        //Create an XmlNodeReader to read the XmlDocument.
        XmlDocument doc = new XmlDocument();
        doc.Load(filename);
        reader = new XmlNodeReader(doc);

        //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(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.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 reader As XmlNodeReader = Nothing
        Try
            'Create an XmlNodeReader to read the XmlDocument.
            Dim doc As New XmlDocument()
            doc.Load(filename)
            reader = New XmlNodeReader(doc)
            
            '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(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.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

此範例會使用 檔案 items.xml ，作為輸入。

<?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: A</Item>
  <!-- Fourteen chars in this element.-->
  <Item>1234567890ABCD</Item>
</Items>

備註

注意

在 .NET Framework 2.0 中，建議的做法是使用 XmlReaderSettings 類別和 Create 方法建立 XmlReader 實例。 這可讓您充分利用.NET Framework中引進的所有新功能。 如需詳細資訊，請參閱參考頁面中的 XmlReader 一節。