Secure Int struct

/// <summary>A secure int which is hard to change using a program like Poke.</summary>
struct secint {
    //public int key { get { return _key; } }
    public int value {
        get { return _value ^ _key; }
        set {
            _key = rng.Next(0, int.MaxValue);
            _value = value ^ _key;
        }
    }

    private System.Random rng;
    private int _key;
    private int _value;

    public secint(int val) {
        rng = new System.Random();
        _key = rng.Next(0, int.MaxValue);
        _value = val ^ _key;
    }
}