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XmlNameTable Class

Table of atomized string objects.

Namespace:  System.Xml
Assembly:  System.Xml (in System.Xml.dll)

Public MustInherit Class XmlNameTable
Dim instance As XmlNameTable

Several classes, such as XmlDocument and XmlReader, use the XmlNameTable class internally to store attribute and element names. When an element or attribute name occurs multiple times in an XML document, it is stored only once in the XmlNameTable.

The names are stored as common language runtime (CLR) object types. This enables you to do object comparisons on these strings rather than a more expensive string comparison. These string objects are referred to as atomized strings.

XmlNameTable is implemented in the NameTable class.

The following example compares two element names.

' Add the element names to the NameTable. 
Dim nt As New NameTable()
Dim book As Object = nt.Add("book")
Dim title As Object = nt.Add("title")

' Create a reader that uses the NameTable. 
Dim settings As New XmlReaderSettings()
settings.NameTable = nt
Dim reader As XmlReader = XmlReader.Create("books.xml", settings)

While reader.Read()
    If reader.NodeType = XmlNodeType.Element Then 
        ' Cache the local name to prevent multiple calls to the LocalName property. 
        Dim localname As Object = reader.LocalName

        ' Do a comparison between the object references. This just compares pointers. 
        If book Is localname Then 
           ' Add additional processing here. 
        End If  
        ' Do a comparison between the object references. This just compares pointers. 
        If title Is localname Then 
           ' Add additional processing here. 
        End If  
    End If 
End While  

' Close the reader.
NameTable* nt = new NameTable();
Object* book = nt->Add(S"book");
Object* price = nt->Add(S"price");

// Create the reader.
XmlReaderSettings* settings = new XmlReaderSettings();
settings->NameTable = nt;
XmlReader* reader = XmlReader::Create(S"books.xml", settings);


 if (System::Object::ReferenceEquals(book, reader->Name)) {
     // Do additional processing.

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0