例外没有序列化

Question

我有这个异常类：

[Serializable]
public class LoginException : Exception
{
    public LoginError LoginError { get; private set; }

    public LoginException(LoginError loginError)
    {
        this.LoginError = loginError;
    }

    public LoginException(SerializationInfo info, StreamingContext context)
    {
        if (info != null)
        {
            this.LoginError = (LoginError)info.GetValue("LoginError", typeof(LoginError));
        }
    }

    public override void GetObjectData(SerializationInfo info, StreamingContext context)
    {
        base.GetObjectData(info, context);

        if (info != null)
        {
            info.AddValue("LoginError", this.LoginError);
        }
    }
}

当我从WebApi操作返回此异常时，我得到以下异常：

System.Runtime.Serialization.SerializationException: Member 'LoginError' was not found. at System.Runtime.Serialization.SerializationInfo.GetElement(String name, Type& foundType) at System.Runtime.Serialization.SerializationInfo.GetValue(String name, Type type)

我在这里缺少什么？