NonSerializedAttribute Class
Indicates that a field of a serializable class should not be serialized. This class cannot be inherited.
For a list of all members of this type, see NonSerializedAttribute Members.
System.Object
System.Attribute
System.NonSerializedAttribute
[Visual Basic] <AttributeUsage(AttributeTargets.Field)> NotInheritable Public Class NonSerializedAttribute Inherits Attribute [C#] [AttributeUsage(AttributeTargets.Field)] public sealed class NonSerializedAttribute : Attribute [C++] [AttributeUsage(AttributeTargets::Field)] public __gc __sealed class NonSerializedAttribute : public Attribute [JScript] public AttributeUsage(AttributeTargets.Field) class NonSerializedAttribute extends Attribute
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.
Remarks
The target objects for the NonSerializedAttribute are public and private fields of a serializable class. By default, classes are not serializable unless they are marked with the SerializableAttribute. During the serialization process all the public and private fields of a class are serialized by default. Fields that are not to be serialized can be marked with the NonSerializedAttribute, which causes the serialization process to exclude the target field during serialization. Alternatively, implement the ISerializable interface to explicitly control the serialization process. Note that classes which implement ISerializable still need to be marked with the SerializableAttribute.
For more information about using attributes, see Extending Metadata Using Attributes.
Example
[Visual Basic, C#, C++] The following example demonstrates serialization of an object marked with the SerializableAttribute attribute, and the behavior of a field marked with the NonSerializedAttribute in the serialized object. To use the BinaryFormatter instead of the SoapFormatter, uncomment the appropriate lines.
[Visual Basic] Imports System Imports System.IO Imports System.Runtime.Serialization Imports System.Runtime.Serialization.Formatters.Soap ''Imports System.Runtime.Serialization.Formatters.Binary Public Class Test Public Shared Sub Main() ' Creates a new TestSimpleObject object. Dim obj As New TestSimpleObject() Console.WriteLine("Before serialization the object contains: ") obj.Print() ' Opens a file and serializes the object into it in binary format. Dim stream As Stream = File.Open("data.xml", FileMode.Create) Dim formatter As New SoapFormatter() ''Dim formatter As New BinaryFormatter() formatter.Serialize(stream, obj) stream.Close() ' Empties obj. obj = Nothing ' Opens file "data.xml" and deserializes the object from it. stream = File.Open("data.xml", FileMode.Open) formatter = New SoapFormatter() ''formatter = New BinaryFormatter() obj = CType(formatter.Deserialize(stream), TestSimpleObject) stream.Close() Console.WriteLine("") Console.WriteLine("After deserialization the object contains: ") obj.Print() End Sub 'Main End Class 'Test ' A test object that needs to be serialized. <Serializable()> Public Class TestSimpleObject Public member1 As Integer Public member2 As String Public member3 As String Public member4 As Double ' A member that is not serialized. <NonSerialized()> Public member5 As String Public Sub New() member1 = 11 member2 = "hello" member3 = "hello" member4 = 3.14159265 member5 = "hello world!" End Sub 'New Public Sub Print() Console.WriteLine("member1 = '{0}'", member1) Console.WriteLine("member2 = '{0}'", member2) Console.WriteLine("member3 = '{0}'", member3) Console.WriteLine("member4 = '{0}'", member4) Console.WriteLine("member5 = '{0}'", member5) End Sub 'Print End Class 'TestSimpleObject [C#] using System; using System.IO; using System.Runtime.Serialization; using System.Runtime.Serialization.Formatters.Soap; //using System.Runtime.Serialization.Formatters.Binary; public class Test { public static void Main() { //Creates a new TestSimpleObject object. TestSimpleObject obj = new TestSimpleObject(); Console.WriteLine("Before serialization the object contains: "); obj.Print(); //Opens a file and serializes the object into it in binary format. Stream stream = File.Open("data.xml", FileMode.Create); SoapFormatter formatter = new SoapFormatter(); //BinaryFormatter formatter = new BinaryFormatter(); formatter.Serialize(stream, obj); stream.Close(); //Empties obj. obj = null; //Opens file "data.xml" and deserializes the object from it. stream = File.Open("data.xml", FileMode.Open); formatter = new SoapFormatter(); //formatter = new BinaryFormatter(); obj = (TestSimpleObject)formatter.Deserialize(stream); stream.Close(); Console.WriteLine(""); Console.WriteLine("After deserialization the object contains: "); obj.Print(); } } // A test object that needs to be serialized. [Serializable()] public class TestSimpleObject { public int member1; public string member2; public string member3; public double member4; // A field that is not serialized. [NonSerialized()] public string member5; public TestSimpleObject() { member1 = 11; member2 = "hello"; member3 = "hello"; member4 = 3.14159265; member5 = "hello world!"; } public void Print() { Console.WriteLine("member1 = '{0}'", member1); Console.WriteLine("member2 = '{0}'", member2); Console.WriteLine("member3 = '{0}'", member3); Console.WriteLine("member4 = '{0}'", member4); Console.WriteLine("member5 = '{0}'", member5); } } [C++] #using <mscorlib.dll> #using <system.dll> #using <system.messaging.dll> #using <System.Runtime.Serialization.Formatters.Soap.dll> using namespace System; using namespace System::IO; using namespace System::Runtime::Serialization::Formatters::Soap; // A test object that needs to be serialized. [Serializable] __gc class TestSimpleObject { int member1; String* member2; String* member3; double member4; public: // A field that is not serialized. [NonSerialized] String* member5; TestSimpleObject() { member1 = 11; member2 = S"hello"; member3 = S"hello"; member4 = 3.14159265; member5 = S"hello world!"; } void Print() { Console::WriteLine(S"member1 = ' {0}'", __box(member1)); Console::WriteLine(S"member2 = ' {0}'", member2); Console::WriteLine(S"member3 = ' {0}'", member3); Console::WriteLine(S"member4 = ' {0}'", __box(member4)); Console::WriteLine(S"member5 = ' {0}'", member5); } }; int main() { //Creates a new TestSimpleObject object. TestSimpleObject* obj = new TestSimpleObject(); Console::WriteLine(S"Before serialization the Object* contains: "); obj->Print(); //Opens a file and serializes the object into it in binary format. Stream* stream = File::Open(S"data.xml", FileMode::Create); SoapFormatter* formatter = new SoapFormatter(); //BinaryFormatter* formatter = new BinaryFormatter(); formatter->Serialize(stream, obj); stream->Close(); //Empties obj. obj = 0; //Opens file S"data.xml" and deserializes the object from it. stream = File::Open(S"data.xml", FileMode::Open); formatter = new SoapFormatter(); //formatter = new BinaryFormatter(); obj = dynamic_cast<TestSimpleObject*>(formatter->Deserialize(stream)); stream->Close(); Console::WriteLine(S""); Console::WriteLine(S"After deserialization the object contains: "); obj->Print(); }
[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button
in the upper-left corner of the page.
Requirements
Namespace: System
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework
Assembly: Mscorlib (in Mscorlib.dll)
See Also
NonSerializedAttribute Members | System Namespace | SerializableAttribute | Attribute | ISerializable | Extending Metadata Using Attributes | XML and SOAP Serialization