25、面向对象设计模式之单例模式——带参单例的调试与理解

public class ParmeraSingleton
{
    private static ParmeraSingleton instance = null;
    public int x, y;
    private ParmeraSingleton(int x, int y)
    {
        this.x = x;
        this.y = y;
    }
    public static ParmeraSingleton GetInstance(int x, int y)
    {
        if (instance == null)
        {
            instance = new ParmeraSingleton(x, y);
        }
        else
        {
            instance.x = x;
            instance.y = y;
        }
        return instance;
    }
}

public class Program
{
        public static void Main(string[] args)
        {
            ParmeraSingleton s1, s2;
            s1 = ParmeraSingleton.GetInstance(1, 2);
            s2 = ParmeraSingleton.GetInstance(2, 3);
            Console.WriteLine(object.ReferenceEquals(s1, s2));
        }
}