XmlValidatingReader.IsEmptyElement 屬性

定義

命名空間:

System.Xml

組件:

System.Xml.ReaderWriter.dll

來源:

XmlValidatingReader.cs

取得值，指出目前的節點是否為空元素 (，例如， <MyElement/>) 。

public:
 virtual property bool IsEmptyElement { bool get(); };

public override bool IsEmptyElement { get; }

member this.IsEmptyElement : bool

Public Overrides ReadOnly Property IsEmptyElement As Boolean

屬性值

Boolean

true 如果目前節點是元素， (NodeType 等於 XmlNodeType.Element 結尾 /> 為 的) 則為 ，否則為 false 。

範例

下列範例會顯示每個專案的文字內容。

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
   XmlTextReader^ txtreader = nullptr;
   XmlValidatingReader^ reader = nullptr;
   try
   {
      
      //Implement the readers.
      txtreader = gcnew XmlTextReader( "elems.xml" );
      reader = gcnew XmlValidatingReader( txtreader );
      
      //Parse the XML and display the text content of each of the elements.
      while ( reader->Read() )
      {
         if ( reader->IsStartElement() )
         {
            if ( reader->IsEmptyElement )
                        Console::WriteLine( "<{0}/>", reader->Name );
            else
            {
               Console::Write( "<{0}> ", reader->Name );
               reader->Read(); //Read the start tag.
               if ( reader->IsStartElement() )
                              
               //Handle nested elements.
               Console::Write( "\r\n<{0}>", reader->Name );
               Console::WriteLine( reader->ReadString() ); //Read the text content of the element.
            }
         }
      }
   }
   finally
   {
      if ( reader != nullptr )
            reader->Close();
   }

}

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

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

    try
    {
       //Implement the readers.
       txtreader = new XmlTextReader("elems.xml");
       reader = new XmlValidatingReader(txtreader);

       //Parse the XML and display the text content of each of the elements.
       while (reader.Read()){
         if (reader.IsStartElement()){
           if (reader.IsEmptyElement)
                    {
                        Console.WriteLine("<{0}/>", reader.Name);
                    }
                    else
                    {
               Console.Write("<{0}> ", reader.Name);
               reader.Read(); //Read the start tag.
               if (reader.IsStartElement())  //Handle nested elements.
                   Console.Write("\r\n<{0}>", reader.Name);
               Console.WriteLine(reader.ReadString());  //Read the text content of the element.
           }
         }
       }
     }

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

Imports System.IO
Imports System.Xml

Public Class Sample
   
   Public Shared Sub Main()
      Dim txtreader As XmlTextReader = Nothing
      Dim reader As XmlValidatingReader = Nothing
      
      Try
         'Implement the readers.
         txtreader = New XmlTextReader("elems.xml")
         reader = New XmlValidatingReader(txtreader)
         
         'Parse the XML and display the text content of each of the elements.
         While reader.Read()
            If reader.IsStartElement() Then
               If reader.IsEmptyElement Then
                  Console.WriteLine("<{0}/>", reader.Name)
               Else
                  Console.Write("<{0}> ", reader.Name)
                  reader.Read() 'Read the start tag.
                  If (reader.IsStartElement())  'Handle nested elements.
                    Console.WriteLine()
                    Console.Write("<{0}>", reader.Name)
                  End If
                  Console.WriteLine(reader.ReadString()) 'Read the text content of the element.
               End If
            End If
         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 elems.xml ，作為輸入。

<book>
  <title>Pride And Prejudice</title>
  <price>19.95</price>
  <misc/>
</book>

備註

注意

類別 XmlValidatingReader 在 .NET Framework 2.0 中已過時。 您可以使用 類別和 Create 方法建立驗證 XmlReader 實例 XmlReaderSettings 。 如需詳細資訊，請參閱 XmlReader 參考頁面的＜備註＞一節。

此屬性可讓您判斷下列各項目之間的差異：

<item num="123"/> IsEmptyElement () true 。

<item num="123"> IsEmptyElement (為 false ，雖然元素內容是空的) 。

不會為空專案產生對應的 EndElement 節點。

如果因為架構驗證而已將預設內容新增至專案， IsEmptyElement 仍會傳 true 回 。 它與專案是否具有預設值沒有關系。 換句話說， IsEmptyElement 只要報告原始檔案中的專案是否具有結束元素標記即可。

另請參閱

• XmlReader