Question

在我的while循环中，它会提示用户输入一个值，输入值后会运行某些方法。我遇到的问题是提示用户输入两次值（即要求输入A，B或X.用户输入值然后程序再次要求输入A，B或X而不执行正确的操作）。任何帮助它进入后操作都会很棒！

         class output
         {
         static void Main(string[] args)
         {
            char userInput;
            char upper;

            Accounts myAccounts = new Accounts();
            myAccounts.input();
            Console.WriteLine("Enter an A to search account numbers");
            Console.WriteLine("Enter a B to average the accounts");
            Console.WriteLine("Enter X to quit the program");
            Console.WriteLine("Enter an option --->");

            userInput = Convert.ToChar(Console.ReadLine());
            upper = char.ToUpper(userInput);

            while (upper != 'X')
            {

                if (upper == 'A')
                {
                    myAccounts.search();
                    Console.WriteLine("Enter an A to search account numbers");
                    Console.WriteLine("Enter a B to average the accounts");
                    Console.WriteLine("Enter X to quit the program");
                    Console.WriteLine("Enter an option --->");
                    userInput = Convert.ToChar(Console.ReadLine());
                    upper = char.ToUpper(userInput);
                }
                else if (upper == 'B')
                {
                    myAccounts.average();
                    Console.WriteLine("Enter an A to search account numbers");
                    Console.WriteLine("Enter a B to average the accounts");
                    Console.WriteLine("Enter X to quit the program");
                    Console.WriteLine("Enter an option --->");
                    userInput = Convert.ToChar(Console.ReadLine());
                    upper = char.ToUpper(userInput);
                }
                else
                    Console.WriteLine("You entered an incorrect option, please select new option");
                Console.WriteLine("Enter an A to search account numbers");
                Console.WriteLine("Enter a B to average the accounts");
                Console.WriteLine("Enter X to quit the program");
                Console.WriteLine("Enter an option --->");
                userInput = Convert.ToChar(Console.ReadLine());
                upper = char.ToUpper(userInput);
            }        
        }
    }

Answer 1

尝试重新格式化您的主要内容：

 static void Main(string[] args)
 {
    char userInput;
    char upper;

    Accounts myAccounts = new Accounts();
    myAccounts.input();

    do
    {

        Console.WriteLine("Enter an A to search account numbers");
        Console.WriteLine("Enter a B to average the accounts");
        Console.WriteLine("Enter X to quit the program");
        Console.WriteLine("Enter an option --->");
        userInput = Convert.ToChar(Console.ReadLine());
        upper = char.ToUpper(userInput);

        if (upper == 'A')
        {
            myAccounts.search();
        }
        else if (upper == 'B')
        {
            myAccounts.average();

        }
        else
            Console.WriteLine("You entered an incorrect option, please select new option");
    }   
    while (upper != 'X')     
}

它并不完美，但却是一个很好的起点。基本上，为什么你看到你的提示两次是因为你在进入while循环之前显示一次菜单，然后在执行操作之后再次显示。我提供的do while循环应该可以解决你的问题。

while循环重复用户输入C＃

1 个答案: