public class CanBeReadOnly<T>
{
    private T _value;

    public CanBeReadOnly(T value)
    {
        _value = value;
    }

    public T Value
    {
        get { return _value; }
        set
        {
            if (!IsReadOnly)
            {
                _value = value;
            }
        }
    }

    public bool IsReadOnly { get; set; }
}