DataContractSerializer Class

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Serializes and deserializes an instance of a type into an XML stream or document using a supplied data contract. This class cannot be inherited.

Inheritance Hierarchy

System.Object
  System.Runtime.Serialization.XmlObjectSerializer
    System.Runtime.Serialization.DataContractSerializer

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

Syntax

'Declaration
Public NotInheritable Class DataContractSerializer _
    Inherits XmlObjectSerializer

public sealed class DataContractSerializer : XmlObjectSerializer

The DataContractSerializer type exposes the following members.

Constructors

	Name	Description
	DataContractSerializer(Type)	Initializes a new instance of the DataContractSerializer class to serialize or deserialize an object of the specified type.
	DataContractSerializer(Type, IEnumerable<Type>)	Initializes a new instance of the DataContractSerializer class to serialize or deserialize an object of the specified type, and a collection of known types that may be present in the object graph.
	DataContractSerializer(Type, String, String)	Initializes a new instance of the DataContractSerializer class to serialize or deserialize an object of the specified type using the supplied XML root element and namespace.
	DataContractSerializer(Type, XmlDictionaryString, XmlDictionaryString)	Initializes a new instance of the DataContractSerializer class to serialize or deserialize an object of the specified type using the XML root element and namespace specified through the parameters of type XmlDictionaryString.
	DataContractSerializer(Type, String, String, IEnumerable<Type>)	Initializes a new instance of the DataContractSerializer class to serialize or deserialize an object of the specified type. This method also specifies the root XML element and namespace in two string parameters as well as a list of known types that may be present in the object graph.
	DataContractSerializer(Type, XmlDictionaryString, XmlDictionaryString, IEnumerable<Type>)	Initializes a new instance of the DataContractSerializer class to serialize or deserialize an object of the specified type. This method also specifies the root XML element and namespace in two XmlDictionaryString parameters as well as a list of known types that may be present in the object graph.

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Properties

	Name	Description
	IgnoreExtensionDataObject	Gets a value that specifies whether to ignore data supplied by an extension of the class when the class is being serialized or deserialized.
	KnownTypes	Gets a collection of types that may be present in the object graph serialized using this instance of the DataContractSerializer.
	MaxItemsInObjectGraph	Gets the maximum number of items in an object graph to serialize or deserialize.
	PreserveObjectReferences	Gets a value that specifies whether to use non-standard XML constructs to preserve object reference data.

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Methods

	Name	Description
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	Finalize	Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	IsStartObject(XmlDictionaryReader)	Determines whether the XmlDictionaryReader is positioned on an object that can be deserialized. (Overrides XmlObjectSerializer.IsStartObject(XmlDictionaryReader).)
	IsStartObject(XmlReader)	Determines whether the XmlReader is positioned on an object that can be deserialized. (Overrides XmlObjectSerializer.IsStartObject(XmlReader).)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ReadObject(Stream)	Reads the XML stream or document with a Stream and returns the deserialized object. (Inherited from XmlObjectSerializer.)
	ReadObject(XmlDictionaryReader)	Reads the XML document or stream with an XmlDictionaryReader and returns the deserialized object. (Inherited from XmlObjectSerializer.)
	ReadObject(XmlReader)	Reads the XML stream with an XmlReader and returns the deserialized object. (Overrides XmlObjectSerializer.ReadObject(XmlReader).)
	ReadObject(XmlDictionaryReader, Boolean)	Reads the XML stream with an XmlDictionaryReader and returns the deserialized object, and also specifies whether a check is made to verify the object name before reading its value. (Overrides XmlObjectSerializer.ReadObject(XmlDictionaryReader, Boolean).)
	ReadObject(XmlReader, Boolean)	Reads the XML stream with an XmlReader and returns the deserialized object, and also specifies whether a check is made to verify the object name before reading its value. (Overrides XmlObjectSerializer.ReadObject(XmlReader, Boolean).)
	ToString	Returns a string that represents the current object. (Inherited from Object.)
	WriteEndObject(XmlDictionaryWriter)	Writes the closing XML element using an XmlDictionaryWriter. (Overrides XmlObjectSerializer.WriteEndObject(XmlDictionaryWriter).)
	WriteEndObject(XmlWriter)	Writes the closing XML element using an XmlWriter. (Overrides XmlObjectSerializer.WriteEndObject(XmlWriter).)
	WriteObject(Stream, Object)	Writes the complete content (start, content, and end) of the object to the XML document or stream with the specified Stream. (Inherited from XmlObjectSerializer.)
	WriteObject(XmlDictionaryWriter, Object)	Writes the complete content (start, content, and end) of the object to the XML document or stream with the specified XmlDictionaryWriter. (Inherited from XmlObjectSerializer.)
	WriteObject(XmlWriter, Object)	Writes all the object data (starting XML element, content, and closing element) to an XML document or stream with an XmlWriter. (Overrides XmlObjectSerializer.WriteObject(XmlWriter, Object).)
	WriteObjectContent(XmlDictionaryWriter, Object)	Writes the XML content using an XmlDictionaryWriter. (Overrides XmlObjectSerializer.WriteObjectContent(XmlDictionaryWriter, Object).)
	WriteObjectContent(XmlWriter, Object)	Writes the XML content using an XmlWriter. (Overrides XmlObjectSerializer.WriteObjectContent(XmlWriter, Object).)
	WriteStartObject(XmlDictionaryWriter, Object)	Writes the opening XML element using an XmlDictionaryWriter. (Overrides XmlObjectSerializer.WriteStartObject(XmlDictionaryWriter, Object).)
	WriteStartObject(XmlWriter, Object)	Writes the opening XML element using an XmlWriter. (Overrides XmlObjectSerializer.WriteStartObject(XmlWriter, Object).)

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Remarks

Use the DataContractSerializer class to serialize and deserialize instances of a type into an XML stream or document. For example, you can create a type named Person with properties that contain essential data, such as a name and address. You can then create and manipulate an instance of the Person class and write all of its property values in an XML document for later retrieval, or in an XML stream for immediate transport. Most important, the DataContractSerializer is used to serialize and deserialize data sent in Silverlight 5 messages. Apply the DataContractAttribute attribute to classes, and the DataMemberAttribute attribute to class members to specify properties and fields that are serialized.

To use the DataContractSerializer, first create an instance of a class and an object appropriate to writing or reading the format; for example, an instance of the XmlDictionaryWriter. Then call the WriteObject method to persist the data. To retrieve data, create an object appropriate to reading the data format (such as an XmlDictionaryReader for an XML document) and call the ReadObject method.

Preparing Classes for Serialization or Deserialization

The DataContractSerializer is used in combination with the DataContractAttribute and DataMemberAttribute classes. To prepare a class for serialization, apply the DataContractAttribute to the class. For each member of the class that returns data that you want to serialize, apply the DataMemberAttribute. You can serialize fields and properties, provided they are publicly accessible.

For example, your schema specifies a Customer with an ID property, but you already have an existing application that uses a type named Person with a Name property. To create a type that conforms to the contract, first apply the DataContractAttribute to the class. Then apply the DataMemberAttribute to every field or property that you want to serialize.

Note:
You can apply the DataMemberAttribute to both private and public members.

The final format of the XML need not be text. Instead, the DataContractSerializer writes the data as an XML infoset, which allows you to write the data to any format recognized by the XmlReader and XmlWriter. It is recommended that you use the XmlDictionaryReader and XmlDictionaryWriter classes to read and write, because both are optimized to work with the DataContractSerializer.

Examples

Namespace SL_DataContractSerializer
    Partial Public Class Page
        Inherits UserControl
        Public Sub New()
            InitializeComponent()
        End Sub

        'This uses an event handler, not Silverlight data binding
        Private Sub OnClick(ByVal sender As Object, ByVal args As EventArgs)
            txtOutput1.Text = "Create a User object and serialize it."
            Dim serializedUser As String = WriteFromObject()
            txtOutput2.Text = serializedUser

        End Sub


        ' Create a User object and serializing it.
        Public Shared Function WriteFromObject() As String
            'Create User object.
            Dim user As New User("Bob", 42)

            'Create a stream to serialize the object to.
            Dim ms As New MemoryStream()

            ' Serializer the User object to the stream.
            Dim ser As New DataContractSerializer(GetType(User))
            ser.WriteObject(ms, user)
            Dim array() As Byte = ms.ToArray()
            ms.Close()
            Return Encoding.UTF8.GetString(array, 0, array.Length)
        End Function

    End Class

    <DataContract> _
    Public Class User
        Private privateName As String
        <DataMember> _
        Public Property Name() As String
            Get
                Return privateName
            End Get
            Set(ByVal value As String)
                privateName = value
            End Set
        End Property
        Private privateAge As Integer
        <DataMember> _
        Public Property Age() As Integer
            Get
                Return privateAge
            End Get
            Set(ByVal value As Integer)
                privateAge = value
            End Set
        End Property

        Public Sub New()
        End Sub

        Public Sub New(ByVal newName As String, ByVal newAge As Integer)
            Name = newName
            Age = newAge
        End Sub


    End Class


End Namespace

namespace SL_DataContractSerializer
{
    public partial class Page : UserControl
    {
        public Page()
        {
            InitializeComponent();
        }

        //This uses an event handler, not Silverlight data binding
        void OnClick(object sender, EventArgs args)
        {
            txtOutput1.Text = "Create a User object and serialize it.";
            string serializedUser = WriteFromObject();
            txtOutput2.Text = serializedUser;

        }


        // Create a User object and serializing it.
        public static string WriteFromObject()
        {
            //Create User object.
            User user = new User("Bob", 42);

            //Create a stream to serialize the object to.
            MemoryStream ms = new MemoryStream();

            // Serializer the User object to the stream.
            DataContractSerializer ser = new DataContractSerializer(typeof(User));
            ser.WriteObject(ms, user);
            byte[] array = ms.ToArray();
            ms.Close();
            return Encoding.UTF8.GetString(array, 0, array.Length);
        }

    }

    [DataContract]
    public class User
    {
        [DataMember]
        public string Name { get; set; }
        [DataMember]
        public int Age { get; set; }

        public User() { }

        public User(string newName, int newAge)
        {
            Name = newName;
            Age = newAge;
        }


    }


}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

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

See Also

Reference

System.Runtime.Serialization Namespace

DataMemberAttribute

DataContractAttribute