A* - Node.cs

class Node : IComparable<Node>
{
    public int H
    {
        get
        {
            return Math.Abs(X - TargetNode.Position.X) +
                   Math.Abs(Y - TargetNode.Position.Y);
        }
    }
    public int G
    {
        get
        {
            if(ParentNode == null)
                return 0;
            return ParentNode.G + 1;
        }
    }
    public int F
    {
        get { return G + H; }
    }
    public int X
    {
        get { return ((int) Position.X); }
    }
    public int Y
    {
        get { return ((int)Position.Y); }
    }
    public Node ParentNode;
    public Node TargetNode;

    public Node (int x, int y)
    {
        Position = new Vector2(x, y);
    }

    public Node(int x, int y, Node parentNode)
    {
        ParentNode = parentNode;
        Position = new Vector2(x, y);
    }

    public int CompareTo(Node node)
    {
        if(F > node.F)
            return 1;

        if(F < node.F)
            return -1;

        return 0;
    }

    public bool Equals(Node node)
    {
        if (X == node.X && Y == node.Y)
            return true;
        return false;
    }

    public static bool operator ==(Node n1, Node n2)
    {
        return n1.Equals(n2);
    }

    public static bool operator !=(Node n1, Node n2)
    {
        return !n1.Equals(n2);
    }
}