XmlValidatingReader.HasValue Property
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.
Gets a value indicating whether the current node can have a Value other than String.Empty.
public:
virtual property bool HasValue { bool get(); };
public override bool HasValue { get; }
member this.HasValue : bool
Public Overrides ReadOnly Property HasValue As Boolean
Property Value
true
if the node on which the reader is currently positioned can have a Value
; otherwise, false
.
Examples
The following example reads in XML with various data types and displays each of the nodes.
#using <System.Xml.dll>
using namespace System;
using namespace System::IO;
using namespace System::Xml;
int main()
{
//Create the validating reader.
XmlTextReader^ txtreader = gcnew XmlTextReader( "book1.xml" );
txtreader->WhitespaceHandling = WhitespaceHandling::None;
XmlValidatingReader^ reader = gcnew XmlValidatingReader( txtreader );
reader->ValidationType = ValidationType::None;
//Parse the file and each node and its value.
while ( reader->Read() )
{
if ( reader->HasValue )
Console::WriteLine( "({0}) {1}={2}", reader->NodeType, reader->Name, reader->Value );
else
Console::WriteLine( "({0}) {1}", reader->NodeType, reader->Name );
}
//Close the reader.
reader->Close();
}
using System;
using System.IO;
using System.Xml;
public class Sample
{
public static void Main()
{
//Create the validating reader.
XmlTextReader txtreader = new XmlTextReader("book1.xml");
txtreader.WhitespaceHandling = WhitespaceHandling.None;
XmlValidatingReader reader = new XmlValidatingReader(txtreader);
reader.ValidationType = ValidationType.None;
//Parse the file and each node and its value.
while (reader.Read())
{
if (reader.HasValue)
Console.WriteLine("({0}) {1}={2}", reader.NodeType, reader.Name, reader.Value);
else
Console.WriteLine("({0}) {1}", reader.NodeType, reader.Name);
}
//Close the reader.
reader.Close();
}
} // End class
Imports System.IO
Imports System.Xml
public class Sample
public shared sub Main()
'Create the validating reader.
Dim txtreader as XmlTextReader = new XmlTextReader("book1.xml")
txtreader.WhitespaceHandling = WhitespaceHandling.None
Dim reader as XmlValidatingReader = new XmlValidatingReader(txtreader)
reader.ValidationType = ValidationType.None
'Parse the file and each node and its value.
while (reader.Read())
if (reader.HasValue) then
Console.WriteLine("({0}) {1}={2}", reader.NodeType, reader.Name, reader.Value)
else
Console.WriteLine("({0}) {1}", reader.NodeType, reader.Name)
end if
end while
'Close the reader.
reader.Close()
end sub
end class
Remarks
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.
The following table lists node types that have a value to return.
Node Type | Value |
---|---|
Attribute |
The value of the attribute. |
CDATA |
The content of the CDATA section. |
Comment |
The content of the comment. |
DocumentType |
The internal subset. |
ProcessingInstruction |
The entire content, excluding the target. |
SignificantWhitespace |
The white space between markup in a mixed content model. |
Text |
The content of the text node. |
Whitespace |
The white space between markup. |
XmlDeclaration |
The content of the declaration. |