ref和out参数

//ref参数示例
 class Test
    {
        static void Swap(ref int x,ref int y)
        {
            Console.WriteLine("进入Swap时：x={0},y={1}",x,y);
            int temp = x;
            x = y;
            y = temp;
            Console.WriteLine("退出Swap时：x={0},y={1}", x, y);
        }
        static void Main()
        {
            int i = 1, j = 2;
            Console.WriteLine("执行Swap前：i={0},j={1}", i, j);
            Swap(ref i,ref j);
            Console.WriteLine("执行Swap后：i={0},j={1}", i, j);
            Console.ReadLine();
        }
    }