Singleton Class

class Program
{
    static void Main()
    {
    SiteStructure s = SiteStructure.Instance;
    }
}

public sealed class SiteStructure
{
    static readonly SiteStructure _instance = new SiteStructure();
    public static SiteStructure Instance
    {
    get
    {
        return _instance;
    }
    }
    SiteStructure()
    {
    // Initialize.
    }
}