XmlValidatingReader.Value 属性

定义

获取当前节点的文本值。

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

属性值

String

返回的值取决于节点的 NodeType。 下表列出具有要返回的值的节点类型。 所有其他节点类型返回 String.Empty。

节点类型 “值”
Attribute 属性的值。
CDATA CDATA 节的内容。
Comment 注释的内容。
DocumentType 内部子集。
ProcessingInstruction 全部内容(不包括指令目标)。
SignificantWhitespace 混合内容模型中标记之间的空白。
Text 文本节点的内容。
Whitespace 标记之间的空白。
XmlDeclaration 声明的内容。

示例

以下示例读取 XML 文件并显示每个节点。

#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

该示例使用该文件 items.xml作为输入。


<?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: &#65;</Item>
  <!-- Fourteen chars in this element.-->
  <Item>1234567890ABCD</Item>
</Items>

注解

备注

XmlValidatingReader在 .NET Framework 2.0 中已过时。 可以使用类和Create方法创建验证XmlReader实例XmlReaderSettings。 有关详细信息,请参阅 XmlReader 引用页的“备注”部分。

适用于

另请参阅