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DataMemberAttribute Class

When applied to the member of a type, specifies that the member is part of a data contract and is serializable by the DataContractSerializer.

System.Object
  System.Attribute
    System.Runtime.Serialization.DataMemberAttribute

Namespace:  System.Runtime.Serialization
Assemblies:   System.Runtime.Serialization (in System.Runtime.Serialization.dll)
  System.Runtime.Serialization.Primitives (in System.Runtime.Serialization.Primitives.dll)

[AttributeUsageAttribute(AttributeTargets.Property|AttributeTargets.Field, Inherited = false, 
	AllowMultiple = false)]
public sealed class DataMemberAttribute : Attribute

The DataMemberAttribute type exposes the following members.

  NameDescription
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsDataMemberAttributeInitializes a new instance of the DataMemberAttribute class.
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  NameDescription
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsEmitDefaultValueGets or sets a value that specifies whether to serialize the default value for a field or property being serialized.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsIsRequiredGets or sets a value that instructs the serialization engine that the member must be present when reading or deserializing.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsNameGets or sets a data member name.
Public propertySupported by Portable Class LibrarySupported in .NET for Windows Store appsOrderGets or sets the order of serialization and deserialization of a member.
Public propertyTypeIdWhen implemented in a derived class, gets a unique identifier for this Attribute. (Inherited from Attribute.)
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  NameDescription
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsEqualsInfrastructure. Returns a value that indicates whether this instance is equal to a specified object. (Inherited from Attribute.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsGetHashCodeReturns the hash code for this instance. (Inherited from Attribute.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodIsDefaultAttributeWhen overridden in a derived class, indicates whether the value of this instance is the default value for the derived class. (Inherited from Attribute.)
Public methodMatchWhen overridden in a derived class, returns a value that indicates whether this instance equals a specified object. (Inherited from Attribute.)
Public methodSupported by Portable Class LibrarySupported in .NET for Windows Store appsToStringReturns a string that represents the current object. (Inherited from Object.)
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  NameDescription
Explicit interface implemetationPrivate method_Attribute.GetIDsOfNamesMaps a set of names to a corresponding set of dispatch identifiers. (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute.GetTypeInfoRetrieves the type information for an object, which can be used to get the type information for an interface. (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute.GetTypeInfoCountRetrieves the number of type information interfaces that an object provides (either 0 or 1). (Inherited from Attribute.)
Explicit interface implemetationPrivate method_Attribute.InvokeProvides access to properties and methods exposed by an object. (Inherited from Attribute.)
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Apply the DataMemberAttribute attribute in conjunction with the DataContractAttribute to identify members of a type that are part of a data contract. One of the serializers that can serialize data contracts is the DataContractSerializer.

The data contract model is an "opt-in" model. Applying the DataMemberAttribute to a field or property explicitly specifies that the member value will be serialized. In contrast, the BinaryFormatter serializes public and private fields of a type, and the XmlSerializer serializes only public fields and properties of a type.

Caution noteCaution

You can apply the DataMemberAttribute to private fields or properties. Be aware that the data returned by the member (even if it private) will be serialized and deserialized, and thus can be viewed or intercepted by a malicious user or process.

By default, the CLR member name is used as the name of the data member. By setting the Name property, you can customize the name of the data member. This can be used to provide a name that may not be allowed as a CLR member name. When mapping to XML using the DataContractSerializer, this name is used as the name of the schema element in a type.

NoteNote

Properties to which the DataMemberAttribute attribute has been applied must have both get and set fields; they cannot be get-only or set-only.

For more information about data contracts and data members, see Using Data Contracts. For more information about member names, see Data Member Default Values.

The following example shows a type to which the DataContractAttribute and DataMemberAttribute attributes have been applied. The Name property on the DataMemberAttribute is set to "ID".

using System;
using System.Collections;
using System.IO;
using System.Runtime.Serialization;
using System.Xml;

// You must apply a DataContractAttribute or SerializableAttribute 
// to a class to have it serialized by the DataContractSerializer.
[DataContract()]
class Person : IExtensibleDataObject
{
    private string LastNameValue;
    // Apply the DataMemberAttribute to fields (or properties)  
    // that must be serialized.
    [DataMember()]
    public string FirstName;

    [DataMember]
    public string LastName
    {
        get { return LastNameValue; }
        set { LastNameValue = value; }
    }

    [DataMember(Name = "ID")]
    public int IdNumber;

    // Note that you can apply the DataMemberAttribute to  
    // a private field as well.
    [DataMember]
    private string Secret;

    public Person(string newfName, string newLName, int newIdNumber)
    {
        FirstName = newfName;
        LastName = newLName;
        IdNumber = newIdNumber;
        Secret = newfName + newLName + newIdNumber;
    }

    // The extensionDataValue field holds data from future versions  
    // of the type.  This enables this type to be compatible with  
    // future versions. The field is required to implement the  
    // IExtensibleDataObject interface. 

    private ExtensionDataObject extensionDatavalue;

    public ExtensionDataObject ExtensionData
    {
        get
        {
            return extensionDatavalue;
        }
        set
        {
            extensionDatavalue = value;
        }
    }
}

public class Test
{
    public static void Main(string[] args)
    {
        try
        {
            WriteObject(@"DataMemberAttributeExample.xml");
            ReadObject(@"DataMemberAttributeExample.xml");
        }
        catch (Exception exc)
        {
            Console.WriteLine(
            "The serialization operation failed: {0} StackTrace: {1}",
            exc.Message, exc.StackTrace);
        }
        finally
        {
            Console.WriteLine("Press <Enter> to exit....");
            Console.ReadLine();
        }
    }

    public static void WriteObject(string filename)
    {
        // Create a new instance of the Person class.
        Person p1 = new Person("Zighetti", "Barbara", 101);
        FileStream writer = new FileStream(filename,
        FileMode.OpenOrCreate);
        DataContractSerializer ser =
            new DataContractSerializer(typeof(Person));
        ser.WriteObject(writer, p1);
        writer.Close();
    }

    public static void ReadObject(string filename)
    {
        // Deserialize an instance of the Person class  
        // from an XML file.
        FileStream fs = new FileStream(filename,
        FileMode.OpenOrCreate);
        DataContractSerializer ser =
            new DataContractSerializer(typeof(Person));
        // Deserialize the data and read it from the instance.
        Person deserializedPerson = (Person)ser.ReadObject(fs);
        fs.Close();
        Console.WriteLine(String.Format("{0} {1}, ID: {2}",
        deserializedPerson.FirstName, deserializedPerson.LastName,
        deserializedPerson.IdNumber));
    }

}

.NET Framework

Supported in: 4.5.3, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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