SerializationInfo.SetType(Type) Metoda

Odwołanie

Definicja

Przestrzeń nazw:: System.Runtime.Serialization

Zestaw:: System.Runtime.dll

Zestaw:: System.Runtime.Serialization.Formatters.dll

Zestaw:: mscorlib.dll

Zestaw:: netstandard.dll

Ważne

Niektóre informacje odnoszą się do produktu w wersji wstępnej, który może zostać znacząco zmodyfikowany przed wydaniem. Firma Microsoft nie udziela żadnych gwarancji, jawnych lub domniemanych, w odniesieniu do informacji podanych w tym miejscu.

Type Ustawia obiekt na serializacji.

public:
 void SetType(Type ^ type);

public void SetType (Type type);

member this.SetType : Type -> unit

Public Sub SetType (type As Type)

Parametry

type: Type

Obiekt Type do serializacji.

Wyjątki

ArgumentNullException

Parametr type ma wartość null.

Przykłady

using namespace System;
using namespace System::IO;
using namespace System::Collections;
using namespace System::Runtime::Serialization::Formatters::Binary;
using namespace System::Runtime::Serialization;

ref class SingletonSerializationHelper;

// There should be only one instance of this type per AppDomain.

[Serializable]
public ref class Singleton sealed: public ISerializable
{
private:

   // This is the one instance of this type.
   static Singleton^ theOneObject = gcnew Singleton;

public:

   // Here are the instance fields.
   String^ someString;
   Int32 someNumber;

private:

   // Private constructor allowing this type to construct the singleton.
   Singleton()
   {
      // Do whatever is necessary to initialize the singleton.
      someString = "This is a String* field";
      someNumber = 123;
   }

public:

   // A method returning a reference to the singleton.
   static Singleton^ GetSingleton()
   {
      return theOneObject;
   }

   // A method called when serializing a Singleton.
   [System::Security::Permissions::SecurityPermissionAttribute
   (System::Security::Permissions::SecurityAction::LinkDemand, 
   Flags=System::Security::Permissions::SecurityPermissionFlag::SerializationFormatter)]
   virtual void GetObjectData( SerializationInfo^ info, StreamingContext context )
   {
      // Instead of serializing this Object*, we will  
      // serialize a SingletonSerializationHelp instead.
      info->SetType( SingletonSerializationHelper::typeid );
      
      // No other values need to be added.
   }

   // NOTE: ISerializable*'s special constructor is NOT necessary 
   // because it's never called
};

[Serializable]
private ref class SingletonSerializationHelper sealed: public IObjectReference
{
public:

   // This Object* has no fields (although it could).
   // GetRealObject is called after this Object* is deserialized
   virtual Object^ GetRealObject( StreamingContext context )
   {
      // When deserialiing this Object*, return a reference to 
      // the singleton Object* instead.
      return Singleton::GetSingleton();
   }
};

[STAThread]
int main()
{
   FileStream^ fs = gcnew FileStream( "DataFile.dat",FileMode::Create );
   try
   {
      // Construct a BinaryFormatter and use it 
      // to serialize the data to the stream.
      BinaryFormatter^ formatter = gcnew BinaryFormatter;

      // Create an array with multiple elements refering to 
      // the one Singleton Object*.
      array<Singleton^>^a1 = {Singleton::GetSingleton(),Singleton::GetSingleton()};

      // This displays S"True".
      Console::WriteLine( "Do both array elements refer to the same Object? {0}", (a1[ 0 ] == a1[ 1 ]) );

      // Serialize the array elements.
      formatter->Serialize( fs, a1 );

      // Deserialize the array elements.
      fs->Position = 0;
      array<Singleton^>^a2 = (array<Singleton^>^)formatter->Deserialize( fs );

      // This displays S"True".
      Console::WriteLine( "Do both array elements refer to the same Object? {0}", (a2[ 0 ] == a2[ 1 ]) );

      // This displays S"True".
      Console::WriteLine( "Do all  array elements refer to the same Object? {0}", (a1[ 0 ] == a2[ 0 ]) );
   }
   catch ( SerializationException^ e ) 
   {
      Console::WriteLine( "Failed to serialize. Reason: {0}", e->Message );
      throw;
   }
   finally
   {
      fs->Close();
   }

   return 0;
}

using System;
using System.Web;
using System.IO;
using System.Collections;
using System.Runtime.Serialization.Formatters.Binary;
using System.Runtime.Serialization;

// There should be only one instance of this type per AppDomain.
[Serializable]
public sealed class Singleton : ISerializable
{
    // This is the one instance of this type.
    private static readonly Singleton theOneObject = new Singleton();

    // Here are the instance fields.
    private string someString_value;
    private Int32 someNumber_value;

   public string SomeString
   {
       get{return someString_value;}
       set{someString_value = value;}
   }

   public Int32 SomeNumber
   {
       get{return someNumber_value;}
       set{someNumber_value = value;}
   }

    // Private constructor allowing this type to construct the Singleton.
    private Singleton()
    {
        // Do whatever is necessary to initialize the Singleton.
        someString_value = "This is a string field";
        someNumber_value = 123;
    }

    // A method returning a reference to the Singleton.
    public static Singleton GetSingleton()
    {
        return theOneObject;
    }

    // A method called when serializing a Singleton.
    void ISerializable.GetObjectData(
        SerializationInfo info, StreamingContext context)
    {
        // Instead of serializing this object,
        // serialize a SingletonSerializationHelp instead.
        info.SetType(typeof(SingletonSerializationHelper));
        // No other values need to be added.
    }

    // Note: ISerializable's special constructor is not necessary
    // because it is never called.
}

[Serializable]
internal sealed class SingletonSerializationHelper : IObjectReference
{
    // This object has no fields (although it could).

    // GetRealObject is called after this object is deserialized.
    public Object GetRealObject(StreamingContext context)
    {
        // When deserializing this object, return a reference to
        // the Singleton object instead.
        return Singleton.GetSingleton();
    }
}

class App
{
    [STAThread]
    static void Main()
    {
        FileStream fs = new FileStream("DataFile.dat", FileMode.Create);

        try
        {
            // Construct a BinaryFormatter and use it
            // to serialize the data to the stream.
            BinaryFormatter formatter = new BinaryFormatter();

            // Create an array with multiple elements refering to
            // the one Singleton object.
            Singleton[] a1 = { Singleton.GetSingleton(), Singleton.GetSingleton() };

            // This displays "True".
            Console.WriteLine(
                "Do both array elements refer to the same object? " +
                (a1[0] == a1[1]));

            // Serialize the array elements.
            formatter.Serialize(fs, a1);

            // Deserialize the array elements.
            fs.Position = 0;
            Singleton[] a2 = (Singleton[]) formatter.Deserialize(fs);

            // This displays "True".
            Console.WriteLine("Do both array elements refer to the same object? "
                + (a2[0] == a2[1]));

            // This displays "True".
            Console.WriteLine("Do all array elements refer to the same object? "
                + (a1[0] == a2[0]));
        }
        catch (SerializationException e)
        {
            Console.WriteLine("Failed to serialize. Reason: " + e.Message);
            throw;
        }
        finally
        {
            fs.Close();
        }
    }
}

Imports System.Web
Imports System.IO
Imports System.Collections
Imports System.Runtime.Serialization.Formatters.Binary
Imports System.Runtime.Serialization
Imports System.Security.Permissions


' There should be only one instance of this type per AppDomain.
<Serializable()> _
<PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
Public NotInheritable Class Singleton
   Implements ISerializable

   ' This is the one instance of this type.
   Private Shared ReadOnly theOneObject As New Singleton

   ' Here are the instance fields.
   Private someString As String
   private someNumber As Int32

   ' Private constructor allowing this type to construct the Singleton.
   Private Sub New()
      ' Do whatever is necessary to initialize the Singleton.
      someString = "This is a string field"
      someNumber = 123
   End Sub

   ' A method returning a reference to the Singleton.
   Public Shared Function GetSingleton() As Singleton
      Return theOneObject
   End Function

   ' A method called when serializing a Singleton.
   <SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.SerializationFormatter)> _
   Private Sub GetObjectData(ByVal info As SerializationInfo, _
      ByVal context As StreamingContext) _
      Implements ISerializable.GetObjectData

      ' Instead of serializing this object, we will  
      ' serialize a SingletonSerializationHelp instead.
      info.SetType(GetType(SingletonSerializationHelper))
      ' No other values need to be added.
   End Sub

   ' Note: ISerializable's special constructor is not necessary 
   ' because it is never called.
End Class


<Serializable()> _
<PermissionSet(SecurityAction.Demand, Name:="FullTrust")> _
Friend NotInheritable Class SingletonSerializationHelper
   Implements IObjectReference
   ' This object has no fields (although it could).

   ' GetRealObject is called after this object is deserialized.
   <SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags:=SecurityPermissionFlag.SerializationFormatter)> _
   Public Function GetRealObject(ByVal context As StreamingContext) As Object Implements IObjectReference.GetRealObject
      ' When deserialiing this object, return a reference to 
      ' the Singleton object instead.
      Return Singleton.GetSingleton()
   End Function
End Class


Class App
   <STAThread()> Shared Sub Main()
      Dim fs As New FileStream("DataFile.dat", FileMode.Create)

      Try
         ' Construct a BinaryFormatter and use it 
         ' to serialize the data to the stream.
         Dim formatter As New BinaryFormatter

         ' Create an array with multiple elements refering to 
         ' the one Singleton object.
         Dim a1() As Singleton = {Singleton.GetSingleton(), Singleton.GetSingleton()}

         ' This displays "True".
         Console.WriteLine("Do both array elements refer to the same object? " & _
            Object.ReferenceEquals(a1(0), a1(1)))

         ' Serialize the array elements.
         formatter.Serialize(fs, a1)

         ' Deserialize the array elements.
         fs.Position = 0
         Dim a2() As Singleton = DirectCast(formatter.Deserialize(fs), Singleton())

         ' This displays "True".
         Console.WriteLine("Do both array elements refer to the same object? " & _
            Object.ReferenceEquals(a2(0), a2(1)))

         ' This displays "True".
         Console.WriteLine("Do all array elements refer to the same object? " & _
            Object.ReferenceEquals(a1(0), a2(0)))
      Catch e As SerializationException
         Console.WriteLine("Failed to serialize. Reason: " & e.Message)
         Throw
      Finally
         fs.Close()
      End Try
   End Sub
End Class

Uwagi

Element Formatter jest odpowiedzialny za ustawienie Type SerializationInfo wystąpienia przed przekazaniem go do klasy GetObjectData. Jednak użytkownicy, którzy chcą wysyłać serwery proxy dla swoich obiektów, będą musieli zmienić typ reprezentowany przez to SerializationInfo wystąpienie. SetType Użycie metody jest równoważne ustawieniu parametru FullTypeName AssemblyNamei .

Dotyczy