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NetDataContractSerializer Class

Serializes and deserializes an instance of a type into XML stream or document using the supplied .NET Framework types. This class cannot be inherited.

Namespace:  System.Runtime.Serialization
Assembly:  System.Runtime.Serialization (in System.Runtime.Serialization.dll)

Public NotInheritable Class NetDataContractSerializer _
	Inherits XmlObjectSerializer _
	Implements IFormatter
Dim instance As NetDataContractSerializer

The NetDataContractSerializer differs from the DataContractSerializer in one important way: the NetDataContractSerializer includes CLR type information in the serialized XML, whereas the DataContractSerializer does not. Therefore, the NetDataContractSerializer can be used only if both the serializing and deserializing ends share the same CLR types.

The serializer can serialize types to which either the DataContractAttribute or SerializableAttribute attribute has been applied. It also serializes types that implement ISerializable.

For more information about serialization, see Using Stand-alone Serialization.

Incompatibility with XElement

The XElement class is used to write XML. However, the NetDataContractSerializer cannot serialize an instance of the type. The following code, therefore, fails with the exception: "Root type 'System.Xml.Linq.XElement' is not supported at the top level by NetDataContractSerializer since it is IXmlSerializable with IsAny=true and must write all its contents including the root element."

Dim fs As New FileStream("mystuff.xml", FileMode.Create, FileAccess.ReadWrite)
Dim myElement As New XElement("Parent", New XElement("child1", "form"), _
    New XElement("child2", "base"), _
    New XElement("child3", "formbase") _
Dim ser As New System.Runtime.Serialization. _
ser.WriteObject(fs, myElement)

However, if an XElement is used as the type of a field or property of a class, the data contained by the field or property is serialized. This is because as a member of a class, the data is not the top level of the class.

The following example code shows a type named Person that is serialized by the NetDataContractSerializer. The DataContractAttribute attribute is applied to the class, and the DataMemberAttribute is applied to members (including a private member) to instruct the NetDataContractSerializer what to serialize.

' You must apply a DataContractAttribute or SerializableAttribute 
' to a class to have it serialized by the NetDataContractSerializer.
<DataContract(Name := "Customer", [Namespace] := "")>  _
Class Person
    Implements IExtensibleDataObject
    <DataMember()>  _
    Public FirstName As String
    <DataMember()>  _
    Public LastName As String
    <DataMember()>  _
    Public ID As Integer 

    Public Sub New(ByVal newfName As String, ByVal newLName As String, _
       ByVal newID As Integer) 
        FirstName = newfName
        LastName = newLName
        ID = newID

    End Sub  

    Private extensionData_Value As ExtensionDataObject

    Public Property ExtensionData() As ExtensionDataObject _
     Implements IExtensibleDataObject.ExtensionData
            Return extensionData_Value
        End Get 
            extensionData_Value = value
        End Set 
    End Property 
End Class  

NotInheritable Public Class Test

    Private Sub New() 

    End Sub 

    Public Shared Sub Main() 

        Catch serExc As SerializationException
            Console.WriteLine("Serialization Failed")
        Catch exc As Exception
            Console.WriteLine("The serialization operation failed: {0} StackTrace: {1}", exc.Message, exc.StackTrace)

            Console.WriteLine("Press <Enter> to exit....")
        End Try 

    End Sub  

    Public Shared Sub WriteObject(ByVal fileName As String) 
        Console.WriteLine("Creating a Person object and serializing it.")
        Dim p1 As New Person("Zighetti", "Barbara", 101)
        Dim fs As New FileStream(fileName, FileMode.Create)
        Dim writer As XmlDictionaryWriter = XmlDictionaryWriter.CreateTextWriter(fs)
        Dim ser As New System.Runtime.Serialization.NetDataContractSerializer()

        ser.WriteObject(writer, p1)

    End Sub      

    Public Shared Sub ReadObject(ByVal fileName As String) 
        Console.WriteLine("Deserializing an instance of the object.")
        Dim fs As New FileStream(fileName, FileMode.Open)
        Dim reader As XmlDictionaryReader = _
           XmlDictionaryReader.CreateTextReader(fs, New XmlDictionaryReaderQuotas())
        Dim ser As New System.Runtime.Serialization.NetDataContractSerializer()

        ' Deserialize the data and read it from the instance. 
        Dim deserializedPerson As Person = CType(ser.ReadObject(reader, True), Person)
        Console.WriteLine(String.Format("{0} {1}, ID: {2}", deserializedPerson.FirstName, deserializedPerson.LastName, deserializedPerson.ID))

    End Sub  
End Class


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 Server 2008 R2, Windows Server 2008, Windows Server 2003

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