Converting BinaryFormatter Binder to DataContractSerializer

Question

How can the Binder property from BinaryFormatter be converted to work with DataContractSerializer in C#?

For example, the code snippet below uses BinaryFormatter:

var bf = new BinaryFormatter();
bf.Binder = new ClassXYZ(); // ClassXYZ inherited from SerializationBinder
var dc = (Class2)bf.Deserialize(stream);

What is the equivalent approach using DataContractSerializer?

Answer 1

Hi @Deepak Rane (drane) , Welcome to Microsoft Q&A,

In C#, DataContractSerializer and BinaryFormatter work differently. BinaryFormatter uses SerializationBinder for type binding, while DataContractSerializer does not support similar binding. Instead, DataContractSerializer uses data contracts ([DataContract] and [DataMember]) for serialization and deserialization, and requires type matching.

You can achieve similar functionality by solving the type binding problem in a custom way.

using System;
using System.IO;
using System.Runtime.Serialization;
using System.Xml;

[DataContract]
public class Class2
{
    [DataMember]
    public string Property { get; set; }
}

public class CustomResolver
{
    public Type ResolveType(string typeName)
    {
        if (typeName == "OldNamespace.Class2")
        {
            return typeof(Class2);
        }
        throw new InvalidOperationException($"Unknown type: {typeName}");
    }
}

public class Program
{
    public static void Main()
    {
        var resolver = new CustomResolver();
        var typeName = "OldNamespace.Class2";
        var resolvedType = resolver.ResolveType(typeName);

        var serializer = new DataContractSerializer(resolvedType);
        using (var stream = new FileStream("data.xml", FileMode.Open))
        {
            var result = serializer.ReadObject(stream);
            var dc = result as Class2;
            Console.WriteLine(dc?.Property);
        }
    }
}

Best Regards,

Jiale

---

If the answer is the right solution, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment". 

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.