Console.WriteLine()重载方法的首选方式为什么是:Currency -》float-》double//书上的例子
为什么不是:Currency -》float   struct Currency
    {
        private delegate string GetAstring(); 
        public uint Dollars;
        public ushort Cents;
        public Currency(uint Dollars, ushort Cents)
        {
            this.Dollars = Dollars;
            this.Cents = Cents;
        }
        public override string ToString()
        {
            return string.Format("${0}.{1,-2:00}", Dollars, Cents);
        }
        public static implicit operator float(Currency value)
        {
            return value.Dollars + (value.Cents / 100.0f);
        }
         static void Main(string[] args)
        {
           
            Currency balance = new Currency(50,35); 
            Console.WriteLine(balance);  //这里有疑问        }