SqlExceptionSerialization.cs

[Test]
public void Can_Serialize_ICommandResult_With_Sql_Exception()
{
  SqlException exception;
            
  try
  {

      throw SqlExceptionCreator.NewSqlException(101);
  } catch(SqlException ex)
  {
      exception = ex;
  }

  var jsonSettings = new JsonSerializerSettings();
  jsonSettings.TypeNameHandling = TypeNameHandling.Auto;

  string serializedResult = JsonConvert.SerializeObject(exception, Formatting.None, jsonSettings);
  var deserializedresult = JsonConvert.DeserializeObject<SqlException>(serializedResult, jsonSettings);
  Assert.AreEqual( exception.ToString(), deserializedresult.ToString());
  Assert.AreEqual(typeof(SqlException), deserializedresult.GetType());
}

public class SqlExceptionCreator
{
    private static T Construct<T>(params object[] p)
    {
        var ctors = typeof(T).GetConstructors(BindingFlags.NonPublic | BindingFlags.Instance);
        return (T)ctors.First(ctor => ctor.GetParameters().Length == p.Length).Invoke(p);
    }

    internal static SqlException NewSqlException(int number = 1)
    {
        SqlErrorCollection collection = Construct<SqlErrorCollection>();
        SqlError error = Construct<SqlError>(number, (byte)2, (byte)3, "server name", "error message", "proc", 100);

        typeof(SqlErrorCollection)
            .GetMethod("Add", BindingFlags.NonPublic | BindingFlags.Instance)
            .Invoke(collection, new object[] { error });


        return typeof(SqlException)
            .GetMethod("CreateException", BindingFlags.NonPublic | BindingFlags.Static,
                null,
                CallingConventions.ExplicitThis,
                new[] { typeof(SqlErrorCollection), typeof(string) },
                new ParameterModifier[] { })
            .Invoke(null, new object[] { collection, "7.0.0" }) as SqlException;
    }
}