代理模式 值代理

Value Proxy

    [DebuggerDisplay("{value*100.0d}%")]
    public struct Perceentage
    {
        private readonly double value; 
        public Perceentage(double value)
        {
            this.value = value;
        }
        public override string ToString()
        {
            return $"{value*100}%";
        }
        public static double operator *(double p1, Perceentage p2)
        {
            return p1 * p2.value;
        }
        public static Perceentage operator +(Perceentage p1, Perceentage p2)
        {
            return new Perceentage(p1.value+p2.value);
        }
    }
    public  static class ExtensitionPerceentage
    {
        public static Perceentage Percent(this int value) 
        {
            return new Perceentage(value / 100.00d);
        }
        public static Perceentage Percent(this double value)
        {
            return new Perceentage(value / 100.00d);
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine(10d * 5.Percent());
            Console.WriteLine(2.Percent() + 3.Percent());
        }
    }