Why Dictionary is serializable ?

a .NET class called KeyedCollection. KeyedCollection derives from the iList interface instead of iDictionary, and is therefore serializable.
So if you need a keyed list and your objects include unique values, you can use KeyedCollection and get the benefits of serialization as well.
You also can check it out:
1.http://www.c-sharpcorner.com/Blogs/BlogDetail.aspx?BlogId=362

Hi

When you are look .net class lib for the dictonarty, it inherited from some basic object. take look the snap shot

using System;

using System.Collections;

using System.Diagnostics;

using System.Reflection;

using System.Runtime.InteropServices;

using System.Runtime.Serialization;

 

namespace System.Collections.Generic

{

    // Summary:

    //     Represents a collection of keys and values.

    //

    // Type parameters:

    //   TKey:

    //     The type of the keys in the dictionary.

    //

    //   TValue:

    //     The type of the values in the dictionary.

    [Serializable]

    [ComVisible(false)]

    [DebuggerDisplay("Count = {Count}")]

    public class Dictionary<TKey, TValue> : IDictionary<TKey, TValue>, ICollection<KeyValuePair<TKey, TValue>>, IEnumerable<KeyValuePair<TKey, TValue>>, IDictionary, ICollection, IEnumerable, ISerializable, IDeserializationCallback

    {

        // Summary:

        //     Initializes a new instance of the System.Collections.Generic.Dictionary

        //     class that is empty, has the default initial capacity, and uses the default

        //     equality comparer for the key type.

        public Dictionary();

        //

        // Summary:

        //     Initializes a new instance of the System.Collections.Generic.Dictionary

        //     class that contains elements copied from the specified System.Collections.Generic.IDictionary

        //     and uses the default equality comparer for the key type.

        //

        // Parameters:

        //   dictionary:

        //     The System.Collections.Generic.IDictionary whose elements are

        //     copied to the new System.Collections.Generic.Dictionary.

        //

        // Exceptions:

        //   System.ArgumentNullException:

        //     dictionary is null.

        //

        //   System.ArgumentException:

        //     dictionary contains one or more duplicate keys.

       

    }

}

 

And it's mark as Serializable

Thank you

dictionery is a collection that inherits from ISerializable this is why :-)