Question

我正在编写一个C＃控制台应用程序，您可以用yyyy / mm / dd格式输入您的姓名和生日，让控制台告诉您年龄和月份的年龄。现在我已经找到了那个部分并且它有效。直到我尝试执行try和catch异常来检查您输入的日期是否格式正确。如果没有，它应该告诉你再次尝试3次，然后告诉你日期格式不正确然后退出应用程序。

现在问题是应用程序的工作类型，但它告诉你日期格式不正确，即使它不是。然后在循环通过要求姓名和出生日期3次的应用程序后仍然继续提供正确的输出。这是我到目前为止的代码（我知道年份输出有点乱）我花了太长时间测试太多东西试图改变它现在，我愿意接受改进和改变）：

namespace CSConsoleDateTimeTypes
{
    class Program
    {
        static int Count = 0;
        static void Main(string[] args)
        { EnterDate(); }
        static void EnterDate()
        {

            string userName, enteredDoBString;
            Console.WriteLine("Enter your name:");
            userName = Console.ReadLine();
            Console.WriteLine("Enter your date of birth in the format yyyy/mm/dd:");
            enteredDoBString = Console.ReadLine();
            string dateString = Console.ReadLine();
            parseDateString(dateString);
            DateTime enteredDoB = DateTime.Parse(enteredDoBString);
            Console.WriteLine("Your DoB is: {0}", enteredDoB);
            DateTime dateToday = DateTime.Today;
            if (dateToday < enteredDoB)
            {
                DateTime date4 = dateToday;
                dateToday = enteredDoB;
                enteredDoB = date4;
            }
            TimeSpan ts = dateToday - enteredDoB;
            //total days (irrelevant to the application though)
            Console.WriteLine(ts.TotalDays);
            //total years
            int years = dateToday.Year - enteredDoB.Year;

            int months = 0;
            //Total months
            if (dateToday.Month < enteredDoB.Month)
            {
                months = 12 - dateToday.Month + enteredDoB.Month;
            }
            else
            {
                months = enteredDoB.Month - dateToday.Month;

            }
            if (months > 12)
            {
                Console.WriteLine("Years: {0}, Months: {1}", years - 1, 12 - (months - 12));
            }
            else if (months < 0)
            {
                Console.WriteLine("Years: {0}, Months: {1}", years, months - months);
            }
            else
            {
                Console.WriteLine("Years: {0}, Months: {1}", years, months);
            }
            Console.ReadKey();
            Console.ReadKey();
        }
        static void parseDateString(string datestring)
        {
            try
            {
                DateTime date3 = DateTime.Parse(datestring, System.Globalization.CultureInfo.InvariantCulture);
                date3.ToShortDateString();
                Console.ReadKey();
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
                //if date was entered incorrectly 3 times, the application should exit..
                Count++;
                if (Count < 3)
                {
                    EnterDate();
                }
                else
                {
                    Console.WriteLine("\aSorry date still not in correct format - Press any key to exit the application");
                    Console.ReadKey();
                }
            }
        }
    }
}

这是我启动应用程序时输出的结果，它在输入后完成所有代码的运行：

Enter your name:
gerrit
Enter your date of birth in the format yyyy/mm/dd:
1997/02/13

String was not recognized as a valid DateTime.
Enter your name:
gerrit
Enter your date of birth in the format yyyy/mm/dd:
1997/02/13

String was not recognized as a valid DateTime.
Enter your name:
gerrit
Enter your date of birth in the format yyyy/mm/dd:
1997/02/13

String was not recognized as a valid DateTime.
Sorry date still not in correct format - Press any key to exit the application
Your DoB is: 1997/02/13 12:00:00 AM
7294
Years: 20, Months: 0
Your DoB is: 1997/02/13 12:00:00 AM
7294
Years: 20, Months: 0
Your DoB is: 1997/02/13 12:00:00 AM
7294
Years: 20, Months: 0

正如您所看到的那样，它要求出生姓名和出生日期3次，并且仍然告诉我日期格式不正确，那么它会给出正确的输出（您的DoB是：1997/02/13 12:00:00 AM 7294 年：20，月：0）3次

它应该询问一次并输出一次，但我无法弄清楚如何做到这一点。任何帮助都将受到高度赞赏。

以下是控制台输出的屏幕截图，如果它有帮助的话

http://i.imgur.com/qUpF0g2.png

Answer 1

我改变了你的代码。

我没有检查过你的其余代码，只是询问了日期。

private static void Main(string[] args)
{
  EnterDate(); 
}

private static void EnterDate()
{
  Console.WriteLine("Enter your name:");
  var userName = Console.ReadLine();

  // ask for date
  var enteredDoBString = AskForDate();
  if (enteredDoBString == null)
    return;

  DateTime enteredDoB = DateTime.Parse(enteredDoBString);
  Console.WriteLine($"Your DoB is: {enteredDoB}");

  DateTime dateToday = DateTime.Today;

  if (dateToday < enteredDoB)
  {
    DateTime date4 = dateToday;
    dateToday = enteredDoB;
    enteredDoB = date4;
  }
  TimeSpan ts = dateToday - enteredDoB;

  // total days (irrelevant to the application though)
  Console.WriteLine(ts.TotalDays);

  // total years
  var years = dateToday.Year - enteredDoB.Year;
  var months = 0;         

  // Total months
  if (dateToday.Month < enteredDoB.Month)
  {
    months = 12 - dateToday.Month + enteredDoB.Month;
  }
  else
  {
    months = enteredDoB.Month - dateToday.Month;
  }

  if (months > 12)
  {
    Console.WriteLine($"Years: {years - 1}, Months: {12 - (months - 12)}");
  }

  else if (months < 0)
  {
    Console.WriteLine($"Years: {years}, Months: {months - months}");
  }

  else
  {
    Console.WriteLine($"Years: {years}, Months: {months}");
  }

  Console.ReadKey();
  Console.ReadKey();
}

private static string AskForDate()
{
  var count = 0;
  while (count++ < 3)
  {
    try
    {
      Console.WriteLine("Enter your date of birth in the format yyyy/mm/dd:");
      return DateTime.Parse(Console.ReadLine(), System.Globalization.CultureInfo.InvariantCulture).ToShortDateString();
    }

    catch (Exception e)
    {
      Console.WriteLine(e.Message);
      //if date was entered incorrectly 3 times, the application should exit..
    }
  }

  Console.WriteLine("\aSorry date still not in correct format - Press any key to exit the application");
  Console.ReadKey();

  return null;
}

我做了什么：

我删除了您的功能parseDateString并创建了一个名为AskForDate的新功能。与名称一样，此函数向用户询问日期，并且在此函数内部，如果有效，则检查输入的日期。我认为最好检查并询问相同的功能。如果用户输入的日期正确，则日期将返回ToShortDateString。如果日期不正确，该函数会再问两次，第三次会返回null。

然后，在EnterDate函数中，如果从null函数返回AskForDate，程序将退出。

我还更改了一些字符串插值，并删除了一些变量。

当我想实现try和catch异常时，代码块重复

1 个答案: