How do I return one item at a time with each button click?

Question

I have an array that I declare above my form load:

protected string[] Colors = new string [3] {\"red\", \"green\", \"orange\"};

When I clic

Answer 1

Track it in a session

 protected void Page_Load(object sender, EventArgs e)
    {           
        int? count = Session["count"] as int?;
        count = (count == null) ? 0 : count;
        Response.Write(Colors[count.Value]);
        count = (count + 1) % Colors.Length;
        Session["count"] = count;
    }