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SerializationInfo Class

Stores all the data needed to serialize or deserialize an object. This class cannot be inherited.

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

'Declaration
<ComVisibleAttribute(True)> _
Public NotInheritable Class SerializationInfo
'Usage
Dim instance As SerializationInfo

/** @attribute ComVisibleAttribute(true) */ 
public final class SerializationInfo
ComVisibleAttribute(true) 
public final class SerializationInfo

This class is used by objects with custom serialization behavior. The GetObjectData method on either ISerializable or ISerializationSurrogate populates the SerializationInfo store with the name, type, and value of each piece of information it wants to serialize. During deserialization, the appropriate function can extract this information.

Objects are added to the SerializationInfo store at serialization time using the AddValue methods and extracted from the SerializationInfo store at deserialization using the GetValue methods.

For more information about customizing serialization, see Custom Serialization.

The following code example demonstrates the SerializationInfo for custom serialization and deserialization of various values.

Imports System
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()> _
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.
   Public someString As String
   Public 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()> _
Friend NotInheritable Class SingletonSerializationHelper
   Implements IObjectReference
   ' This object has no fields (although it could).

   ' GetRealObject is called after this object is deserialized.
   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()
        Run()
    End Sub

    Shared Sub Run()
        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

System.Object
  System.Runtime.Serialization.SerializationInfo

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

Windows 98, Windows 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

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