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SerializationInfoEnumerator Class

Provides a formatter-friendly mechanism for parsing the data in SerializationInfo. This class cannot be inherited.

System.Object
  System.Runtime.Serialization.SerializationInfoEnumerator

Namespace:  System.Runtime.Serialization
Assembly:  mscorlib (in mscorlib.dll)
[ComVisibleAttribute(true)]
public sealed class SerializationInfoEnumerator : IEnumerator

The SerializationInfoEnumerator type exposes the following members.

  Name Description
Public property Current Gets the item currently being examined.
Public property Name Gets the name for the item currently being examined.
Public property ObjectType Gets the type of the item currently being examined.
Public property Value Gets the value of the item currently being examined.
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  Name Description
Public method Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method MoveNext Updates the enumerator to the next item.
Public method Reset Resets the enumerator to the first item.
Public method ToString Returns a string that represents the current object. (Inherited from Object.)
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  Name Description
Explicit interface implemetation Private property IEnumerator.Current Gets the current item in the collection.
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The current class is a standard enumerator that parses over the values stored in SerializationInfo. Instead of recording the values, the SerializationInfoEnumerator keeps pointers to the member variables of the SerializationInfo that created it.

This class follows the IEnumerator mechanism.

The following code example shows how to use the FormatterServices class in order to properly serialize or deserialize an object where the base class does not implement ISerializable but the derived class does.


using System;
using System.IO;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters;
using System.Runtime.Serialization.Formatters.Binary;
using System.Reflection;
using System.Security.Permissions;


// Person is a serializable base class.
[Serializable]
public class Person
{
    private String title;

    public Person(String title)
    {
        this.title = title;
    }

    public override String ToString()
    {
        return String.Format("{0}", title);
    }
}

// Employee is a serializable class derived from Person.
[Serializable]
public class Employee : Person
{
    private String title;

    public Employee(String title) : base("Person")
    {
        this.title = title;
    }

    public override String ToString()
    {
        return String.Format("{0} -> {1}", title, base.ToString());
    }
}

// Manager is a serializable and ISerializable class derived from Employee.
[Serializable]
public class Manager : Employee, ISerializable
{
    private String title;

    public Manager() : base("Employee") 
    {
        this.title = "Manager";
    }

    [SecurityPermission(SecurityAction.Demand, SerializationFormatter = true)]
    public void GetObjectData(SerializationInfo info, StreamingContext context)
    {

        // Serialize the desired values for this class.
        info.AddValue("title", title);

        // Get the set of serializable members for the class and base classes.
        Type thisType = this.GetType();
        MemberInfo[] mi = FormatterServices.GetSerializableMembers(thisType, context);

        // Serialize the base class's fields to the info object.
        for (Int32 i = 0; i < mi.Length; i++)
        {
            // Do not serialize fields for this class.
            if (mi[i].DeclaringType == thisType) continue;

            // Skip this field if it is marked NonSerialized.
            if (Attribute.IsDefined(mi[i], typeof(NonSerializedAttribute))) continue;

            // Get the value of this field and add it to the SerializationInfo object.
            info.AddValue(mi[i].Name, ((FieldInfo) mi[i]).GetValue(this));
        }

        // Call the method below to see the contents of the SerializationInfo object.
        DisplaySerializationInfo(info);
    }

    private void DisplaySerializationInfo(SerializationInfo info)
    {
        SerializationInfoEnumerator e = info.GetEnumerator();
        Console.WriteLine("Values in the SerializationInfo:");
        while (e.MoveNext())
        {
            Console.WriteLine("Name={0}, ObjectType={1}, Value={2}", e.Name, e.ObjectType, e.Value);
        }
    }

    [SecurityPermissionAttribute(SecurityAction.Demand, Flags=SecurityPermissionFlag.SerializationFormatter)]
    protected Manager(SerializationInfo info, StreamingContext context) : base(null)
    {

        // Get the set of serializable members for the class and base classes.
        Type thisType = this.GetType();
        MemberInfo[] mi = FormatterServices.GetSerializableMembers(thisType, context);

        // Deserialize the base class's fields from the info object.
        for (Int32 i = 0; i < mi.Length; i++)
        {
            // Do not deserialize fields for this class.
            if (mi[i].DeclaringType == thisType) continue;

            // For easier coding, treat the member as a FieldInfo object
            FieldInfo fi = (FieldInfo) mi[i];

            // Skip this field if it is marked NonSerialized.
            if (Attribute.IsDefined(mi[i], typeof(NonSerializedAttribute))) continue;

            // Get the value of this field from the SerializationInfo object.
            fi.SetValue(this, info.GetValue(fi.Name, fi.FieldType));
        }

        // Deserialize the values that were serialized for this class.
        title = info.GetString("title");
    }

    public override String ToString()
    {
        return String.Format("{0} -> {1}", title, base.ToString());
    }
}


public sealed class App
{
    public static void Main()
    {
        Run();
    }

    public static void Run()
    {
        using (Stream stream = new MemoryStream())
	{
            IFormatter formatter = new BinaryFormatter();
            Manager m = new Manager();
            Console.WriteLine(m.ToString());
            formatter.Serialize(stream, m);

            stream.Position = 0;
            m = (Manager) formatter.Deserialize(stream);
            Console.WriteLine(m.ToString());
        }
    }
}
// This code produces the following output.
//
//  Manager -> Employee -> Person
//  Values in the SerializaitonInfo:
//  Name=title, ObjectType=System.String, Value=Manager
//  Name=Employee+title, ObjectType=System.String, Value=Employee
//  Name=Person+title, ObjectType=System.String, Value=Person
//  Manager -> Employee -> Person


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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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