NonSerializedAttribute Classe

Definizione

public ref class NonSerializedAttribute sealed : Attribute

[System.AttributeUsage(System.AttributeTargets.Field, Inherited=false)]
public sealed class NonSerializedAttribute : Attribute

[System.AttributeUsage(System.AttributeTargets.Field, Inherited=true)]
public sealed class NonSerializedAttribute : Attribute

[System.AttributeUsage(System.AttributeTargets.Field, Inherited=false)]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class NonSerializedAttribute : Attribute

[<System.AttributeUsage(System.AttributeTargets.Field, Inherited=false)>]
type NonSerializedAttribute = class
    inherit Attribute

[<System.AttributeUsage(System.AttributeTargets.Field, Inherited=true)>]
type NonSerializedAttribute = class
    inherit Attribute

[<System.AttributeUsage(System.AttributeTargets.Field, Inherited=false)>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type NonSerializedAttribute = class
    inherit Attribute

Public NotInheritable Class NonSerializedAttribute
Inherits Attribute

Ereditarietà

Object

Attribute

NonSerializedAttribute

Attributi

AttributeUsageAttribute ComVisibleAttribute

Esempio

Nell'esempio seguente viene illustrata la serializzazione di un oggetto contrassegnato con l'attributo SerializableAttribute e il comportamento di un campo contrassegnato con l'oggetto NonSerializedAttribute serializzato.

#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]
ref class TestSimpleObject
{
private:
   int member1;
   String^ member2;
   String^ member3;
   double member4;

public:

   // A field that is not serialized.

   [NonSerialized]
   String^ member5;
   TestSimpleObject()
   {
      member1 = 11;
      member2 = "hello";
      member3 = "hello";
      member4 = 3.14159265;
      member5 = "hello world!";
   }

   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 );
   }

};

int main()
{
   // Creates a new TestSimpleObject object.
   TestSimpleObject^ obj = gcnew 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 = gcnew SoapFormatter;

   //BinaryFormatter* formatter = new BinaryFormatter();
   formatter->Serialize( stream, obj );
   stream->Close();

   // Empties obj.
   obj = nullptr;

   // Opens file S"data.xml" and deserializes the object from it.
   stream = File::Open( "data.xml", FileMode::Open );
   formatter = gcnew SoapFormatter;

   //formatter = new BinaryFormatter();
   obj = dynamic_cast<TestSimpleObject^>(formatter->Deserialize( stream ));
   stream->Close();
   Console::WriteLine( "" );
   Console::WriteLine( "After deserialization the object contains: " );
   obj->Print();
}

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);
    }
}

open System
open System.IO
open System.Runtime.Serialization.Formatters.Soap

// A test object that needs to be serialized.
[<Serializable>]
type TestSimpleObject() =
    let member1 = 11
    let member2 = "hello"
    let member3 = "hello"
    let member4 = 3.14159265

    // A field that is not serialized.
    [<NonSerialized>]
    let member5 = "hello world!"

    member _.Print() =
        printfn $"member1 = '{member1}'"
        printfn $"member2 = '{member2}'"
        printfn $"member3 = '{member3}'"
        printfn $"member4 = '{member4}'"
        printfn $"member5 = '{member5}'"

[<EntryPoint>]
let main _ =
    // Creates a new TestSimpleObject object.
    let obj = TestSimpleObject()

    printfn "Before serialization the object contains: "
    obj.Print()

    // Opens a file and serializes the object into it in binary format.
    let stream = File.Open("data.xml", FileMode.Create)
    let formatter = SoapFormatter()

    //BinaryFormatter formatter = new BinaryFormatter()

    formatter.Serialize(stream, obj)
    stream.Close()

    // Opens file "data.xml" and deserializes the object from it.
    let stream = File.Open("data.xml", FileMode.Open)
    let formatter = new SoapFormatter()

    let obj = formatter.Deserialize stream :?> TestSimpleObject
    stream.Close()

    printfn "\nAfter deserialization the object contains: "
    obj.Print()
    0

Imports System.IO
Imports System.Runtime.Serialization
Imports System.Runtime.Serialization.Formatters.Soap




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()
      


      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()



      obj = CType(formatter.Deserialize(stream), TestSimpleObject)
      stream.Close()
      
      Console.WriteLine("")
      Console.WriteLine("After deserialization the object contains: ")
      obj.Print()

   End Sub

End Class


' 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
      
   
   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

End Class

Commenti

Quando si usano le BinaryFormatter classi o SoapFormatter per serializzare un oggetto, usare l'attributo NonSerializedAttribute per impedire la serializzazione di un campo. Ad esempio, è possibile usare questo attributo per impedire la serializzazione dei dati sensibili.

Gli oggetti di destinazione per l'attributo NonSerializedAttribute sono campi pubblici e privati di una classe serializzabile. Per impostazione predefinita, le classi non sono serializzabili a meno che non siano contrassegnate con SerializableAttribute. Durante il processo di serializzazione tutti i campi pubblici e privati di una classe vengono serializzati per impostazione predefinita. I campi contrassegnati con NonSerializedAttribute sono esclusi durante la serializzazione. Se si usa la classe per serializzare un oggetto, usare la XmlSerializer XmlIgnoreAttribute classe per ottenere la stessa funzionalità. In alternativa, implementare l'interfaccia per controllare in modo esplicito il ISerializable processo di serializzazione. Si noti che le classi che implementano ISerializable devono comunque essere contrassegnate con SerializableAttribute.

Per applicare la classe a un evento, impostare la posizione dell'attributo NonSerializedAttribute sul campo, come illustrato nel codice C# seguente.

[field:NonSerializedAttribute()]   
public event ChangedEventHandler Changed;  

Se un campo non è serializzato, ma richiede comunque un valore predefinito che deve essere fornito dopo la deserializzazione, è possibile creare un metodo che fornisce il campo con un valore, quindi applicare il OnDeserializedAttribute al metodo.

Per altre informazioni sull'uso degli attributi, vedere Attributi.

Costruttori

Proprietà

Metodi

Implementazioni dell'interfaccia esplicita

Si applica a

Vedi anche

• SerializableAttribute
• Attribute
• ISerializable
• Estensione di metadati mediante attributi
• Serializzazione SOAP e XML