C＃条件语句

Question

我正在处理有条件的声明，并且很难在Windows Studio 2022中正确运行我的小型运输控制台。用户选择路线或选择不购买票证。

 {
   Console.WriteLine("Would you like to buy a Ticket?\n");
   Console.WriteLine("Please Type 1 for: Yes");
   Console.WriteLine("Please Type 2 for: No");
   var response = Console.ReadLine();
   Console.WriteLine(response);
   int num = 1;
   if (num == 1)
   {
     Console.WriteLine("1) For the first route option, please type 1");
     Console.WriteLine("2) For the second route option, please type 2");
   }
   int num2 = 2;
   if (num2 == 2)
   {
     Console.WriteLine("No Ticket Purchased: Have a great day!");
   }
   else
   {
     Console.WriteLine("Your answer was not vaild");
   }

Answer 1

我希望您的代码看起来像这样 - 您检查响应值。

 {
   Console.WriteLine("Would you like to buy a Ticket?\n");
   Console.WriteLine("Please Type 1 for: Yes");
   Console.WriteLine("Please Type 2 for: No");
   var response = Console.ReadLine();
   Console.WriteLine(response);


   if (response == '1')
   {
      // do something to let them buy a ticket
   }
   else
     if (response == '2')
     {
        Console.WriteLine("No Ticket Purchased: Have a great day!");
     }
     else
     {
       Console.WriteLine("Your answer was not vaild");
     }
  } 

Answer 2

1. 您正在读取称为响应的变量中的数据，并且永远不会使用它。
2. 您正在使用Value 1 和NUM2的变量NUM1中设置数据，并使用 2 进行检查，您正在检查它们在条件下，在中。

您可以尝试创建函数以在IF-ELSE块中执行，以使您对代码的可读性更好。

Answer 3

首先，我在此页面上看到的答案是正确的。
看来您忘记了响应的使用。
但是我很难理解您的问题。
您将响应声明为VAR，然后决定使用INT。
没问题，如果愿意，可以做到。
但是，如果您想使用int，则需要将其放入try-catch块中，以免获得异常，以防用户输入字符串。
当您将VAR转换为INT时，此例外将会得到。
我添加了一些评论来解释代码。
如果您有疑问 - 请不要犹豫。
祝你好运 ！

private static void BuyTicket(bool retry = true)
    {
        int selection = 0;
        Console.WriteLine("Would you like to buy a Ticket?\n");
        Console.WriteLine("Please Type 1 for: Yes");
        Console.WriteLine("Please Type 2 for: No");
        var response = Console.ReadLine();
        //for case user enter a string and not a number,  so need to give friendly message of the options available
        try
        {
            selection = int.Parse(response);
        }
        catch (Exception ex)
        {
            Console.WriteLine("Please choose '1' or '2' only");
            Console.WriteLine(ex.Message);
            if (retry == true)
            {
                //if the user will enter invalid data this time , it will skip and continue
                BuyTicket(false);
            }                
        }            
        if (selection == 1)
        {
            Console.WriteLine("You choosed to buy a ticket.");
            Console.WriteLine("1) For the first route option, please type 1");
            Console.WriteLine("2) For the second route option, please type 2");
            response = Console.ReadLine();
            Console.WriteLine("Thanks for your choice. You choose " + int.Parse(response) + " route option");
        }
       
        else if (selection == 2)
        {
            Console.WriteLine("No Ticket Purchased: Have a great day!");
        }
        else
        {
            Console.WriteLine("Your answer was not vaild. Please enter '1' or '2' only");
        }
    }