一个方法可以在运行时确定参数是否已被默认？ [重复]

Question

这个问题在这里已有答案：

• Check inside method whether some optional argument was passed 10个答案

给定这个示例代码，方法foo有没有办法在运行时确定第4个参数是否已被默认？

using System;

namespace DefaultParameters {
    class Program {
        static void Main(string[] args) {
            int a = 0,b = 1,c = 3;
            foo(a, b, c);       // The 4th parm is defaulted in the method definition.
            foo(a, b, c, 100);  // The 4th parm is explicit in the method call.
        }

        /// <summary>
        /// A method with a default paramater
        /// </summary>
        /// <param name="speed">Speed</param>
        /// <param name="brightness">Brightness</param>
        /// <param name="weight">Weight</param>
        /// <param name="humidity">Humidity</param>
        public static void foo(int speed, int brightness, int weight, int humidity = 42) {
            Console.WriteLine("speed = " + speed + " brightness = " + brightness + " weight = " + weight + " humidity  = " + humidity);
        }
    }
}

Answer 1

No

你可以采取一些自由，并猜测如果它是默认值，它可能没有给出，但没有办法确定。