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XmlTextReader.ReadString Method

Definition

Reads the contents of an element or a text node as a string.

public:
 override System::String ^ ReadString();
public override string ReadString ();
override this.ReadString : unit -> string
Public Overrides Function ReadString () As String

Returns

The contents of the element or text node. This can be an empty string if the reader is positioned on something other than an element or text node, or if there is no more text content to return in the current context.

Note: The text node can be either an element or an attribute text node.

Exceptions

An error occurred while parsing the XML.

An invalid operation was attempted.

Examples

The following example displays the text content of each element.

#using <System.Xml.dll>

using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
   XmlTextReader^ reader = nullptr;
   try
   {
      
      //Load the reader with the XML file.
      reader = gcnew XmlTextReader( "elems.xml" );
      
      //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 reader = null;

    try
    {
       //Load the reader with the XML file.
       reader = new XmlTextReader("elems.xml");

       //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
Option Strict
Option Explicit

Imports System.IO
Imports System.Xml

Public Class Sample
    
    Public Shared Sub Main()
        Dim reader As XmlTextReader = Nothing
        
        Try
            'Load the reader with the XML file.
            reader = New XmlTextReader("elems.xml")
            
            '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

The example uses the file, elems.xml, as input.


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

Remarks

Note

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.

If positioned on an element, ReadString concatenates all text, significant white space, white space, and CData section node types together and returns the concatenated data as the element content. It stops when any markup is encountered, including comments and processing instructions. This could occur in a mixed content model, or when an element end tag is read.

If positioned on a text node, ReadString performs the same concatenation from the text node to the element end tag. If the reader is positioned on an attribute text node, ReadString has the same functionality as if the reader were position on the element start tag. It returns all the concatenated element text nodes.

Applies to

See also