XmlValidatingReader.ReadString Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Reads the contents of an element or 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.
Examples
The following example displays the text content of each of the elements.
#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
The example uses the file, elems.xml
, as input.
<book>
<title>Pride And Prejudice</title>
<price>19.95</price>
<misc/>
</book>
Remarks
The text node can be either an element or an attribute text node.
Note
The XmlValidatingReader class is obsolete in .NET Framework 2.0. You can create a validating XmlReader instance by using the XmlReaderSettings class and the Create method. For more information, see the Remarks section of the XmlReader reference page.
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. The reader 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.
The EntityHandling property determines how ReadString
works as follows:
Value | Description |
---|---|
ExpandEntities | Returns expanded character and general entities. This is the default. |
ExpandCharEntities | Returns the text content up to but not including a general entity reference. This means a general entity causes ReadString to stop. You must call Read to step over the entity reference. |