错误& # 39;Program.Number& # 39;是'类型'But用作'变量

程序错误。数字'是一个'类型'，但像'变量'一样使用

当我试图运行这个程序时，我一直得到上面的错误，我做错了什么

using System;
class Program
{
    enum Number{ standard = 1, express = 2, same = 3};
    const int A = 1, B = 2;
    const int Y = 3, N = 4;
    static void Main()
     {
        double cost, LB;
        int numValues, Number_of_items ;
         Console.WriteLine("please enter the type of shiping you want");
        Console.WriteLine("Enter 1:standard shipping.");
        Console.WriteLine("Enter 2:express shipping.");
        Console.WriteLine("Enter 3:same day shipping.");

        switch ((Number))
        { 
            case Numbers.standard:
                Console.WriteLine("thankyou for chooseing standerd shipping");
                Console.WriteLine("please choose a catagory");
                Console.Write("Type A or B to make your selection");
                {      if (A==A)
                {
                    Console.Write("please enter the number of items");
                    Number_of_items = int.Parse(Console.ReadLine());
                    cost = 3 * Number_of_items;
                    Console.Write("is this shipment going to alaska or Hawaii? (y or n)");
                    if (Y==Y)
                    {
                        cost = cost + 2.50;
                        Console.WriteLine("Total cost is {0}." , cost);
                    }
                    else 
                        Console.WriteLine("total cost is {0}." , cost);

                }
                else 
                Console.Write("please enter the weiht in pounds");
               LB =  double.Parse(Console.ReadLine());
                cost = 1.45 * LB;
                Console.WriteLine("is this shipment going to alaska or Hawaii? (y or n)");
        }
                if (Y==Y)
                {
                    cost = cost + 2.50;
                        Console.WriteLine("Total cost is {0}." , cost);
                }
                else 
                        Console.WriteLine("total cost is {0}." , cost);
                break;

                case Numbers.express:
                Console.WriteLine("thankyou for chooseing Express Shipping");
                Console.WriteLine("please choose a catagory");
                Console.Write("Type A or B to make your selection");
                    {       if (A==A)
                        Console.Write("please enter the number of items");
                        Number_of_items = int.Parse(Console.ReadLine());
                        cost = 4 * Number_of_items;
                        {
                    Console.Write("is this shipment going to alaska or Hawaii? (y or n)");
                    if (Y==Y)
                    {
                        cost = cost + 5.00;
                        Console.WriteLine("Total cost is {0}." , cost);
                    }
                    else 
                        Console.WriteLine("total cost is {0}." , cost);

                    }
                     if(B==B) 
                Console.Write("please enter the weiht in pounds");
               LB =  double.Parse(Console.ReadLine());
                cost = 2.50 * LB;
                Console.WriteLine("is this shipment going to alaska or Hawaii? (y or n)");
                    }
                if (Y==Y)
                {
                    cost = cost + 5.00;
                        Console.WriteLine("Total cost is {0}." , cost);
                }
                else 
                        Console.WriteLine("total cost is {0}." , cost);
            break;


                case Numbers.same:
                Console.WriteLine("thankyou for chooseing Same Day Shipping");
                Console.WriteLine("please choose a catagory");
                Console.Write("Type A or B to make your selection");
                if (A == A)
                    Console.Write("please enter the number of items");
                    Number_of_items = int.Parse(Console.ReadLine());
                    cost = 5.50 * Number_of_items;
                    Console.Write("is this shipment going to alaska or Hawaii? (y or n)");
                    if (Y==Y)
                    {
                        cost = cost + 8.00;
                        Console.WriteLine("Total cost is {0}." , cost);
                    }
                    else 
                        Console.WriteLine("total cost is {0}." , cost);

                if (B==B)
                Console.Write("please enter the weiht in pounds");
               LB =  double.Parse(Console.ReadLine());
                cost = 3.00 * LB;
                Console.WriteLine("is this shipment going to alaska or Hawaii? (y or n)");
                if (Y==Y)
                {
                    cost = cost + 8.00;
                        Console.WriteLine("Total cost is {0}." , cost);
                }
                else 
                        Console.WriteLine("total cost is {0}." , cost);
                break;
        }

        numValues = 1; 








   Console.ReadLine();
    }//End Main()
}//End class Program

switch((Number))

int input;
while(!int.TryParse(Console.ReadLine(), ref input) || input < 1 || input > 3) {
    Console.WriteLine("Please enter a valid option!");
}
switch((Number)input)

switch ((Number)myNumber)