Serialisation constructor

Context: If your custom exception may be serialized (e.g., across AppDomains, in remoting, or in logs), you must implement a special constructor that takes SerializationInfo and StreamingContext. This constructor is called during deserialization and should pass the parameters to the base constructor. Also apply the [Serializable] attribute.

Usage Example

using System;
using System.Runtime.Serialization;

[Serializable]
public class SerializableException : Exception
{
    public SerializableException() { }

    public SerializableException(string message) : base(message) { }

    public SerializableException(string message, Exception inner) : base(message, inner) { }

    // Serialisation constructor
    protected SerializableException(SerializationInfo info, StreamingContext context)
        : base(info, context)
    {
    }
}

class Program
{
    static void Main()
    {
        var ex = new SerializableException("Test");
        Console.WriteLine(ex.Message);
    }
}

Output console

dotnet run
Test

Important notes

• The serialisation constructor must be protected or public.
• It should always call base(info, context).
• Required for exceptions that cross boundaries (e.g., in microservices, WCF).

Real-world usage example

Distributed systems – Custom exceptions in a library used by multiple services need serialisation to preserve error details.
See .NET docs on serialisation constructors.

Related sections

• 12.3.1 Derive from Exception
• 12.3.3 Adding custom properties