private static void Main(string[] args) { Test1 t1 = new Test1(100); Console.Write("初始"); t1.DisplayValue(); Console.Write("修改后"); int x = t1.value; x = 200; t1.DisplayValue(); Test2 t2 = new Test2(100); Console.Write("初始"); t2.DisplayValue(); Console.Write("修改后"); ref int y = ref t2.value;