c#---ref参数

员工基本工资为5000元，奖金方法+500元，调用该方法之后为什么工资还是5000元？

static void Main(string[] args)
        {
            double salary = 5000;
            jiangJin(salary);
            Console.WriteLine(salary);
            Console.ReadKey();
        }

        public static void jiangJin(double salary)
        {
            salary += 500;
        }

5500的正确代码写法，是不是有点麻烦呢？

static void Main(string[] args)
        {
            double salary = 5000;
            double d = jiangJin(salary);
            Console.WriteLine(d);
            Console.ReadKey();
        }

        public static double jiangJin(double salary)
        {
            salary += 500;
            return salary;
        }

ref参数：将变量带入一个方法中改变之后在带出方法

注意事项：

ref参数在方法外也就是调用方法之前必须为其赋值

 static void Main(string[] args)
        {
            double salary = 5000;
            jiangJin(ref salary);
            Console.WriteLine(salary);
            Console.ReadKey();
        }
        public static void jiangJin(ref double salary)
        {
            salary += 500;

        }

ref参数在变量交换中的示例

 static void Main(string[] args)
        {
            int n1 = 10;
            int n2 = 100;
            Program.Test(ref n1, ref n2);
            Console.WriteLine(n1);
            Console.WriteLine(n2);
            Console.ReadKey();
        }

        public static void Test(ref int n1, ref int n2)
        {
            int temp = n1;
            n1 = n2;
            n2 = temp;
        }