c#:优化输入控制台的错误预防

我试图从你的代码中删除一些do while循环。你在找这个吗?

public static void Main()
{
    int[] selection = new int[] //array for the age requirements of each film
    {
    15, 15, 12, 18, 0
    };
    string filmNumberText; //console input for the film number 
    int filmNumber; //input string parsed as integer 
    string ageText; //console input for age
    int age; //parsed age string
    int ageLimit; //age requirement for selected film
    Console.Write("Welcome to our Multiplex.'n'n");
    Console.WriteLine(@"We are presently showing:
1. Rush (15) 
2. How I Live Now (15)
3. Thor: The Dark World (12A)
4. Filth (18)
5. Planes (U)");
    do  //loops as long as input is not between 1 and 5
    {
        Console.Write("'nEnter the number of the film you wish to see: ");
        filmNumberText = Console.ReadLine();
    } while (int.TryParse(filmNumberText, out filmNumber) == false || (filmNumber < 1 || filmNumber > 5));
    filmNumber = filmNumber - 1; //changes input from 1-5 to 0-4
    ageLimit = selection[filmNumber]; //selects age requirement from array
    //loops as long as input is not an integer
    do
    {
        Console.Write("'nPlease enter an age between 0 and 125:");
        ageText = Console.ReadLine();
    } while (int.TryParse(ageText, out age) == false || (age < 0 || age > 125)); //check again if input is an integer
    if (age < ageLimit) //if too young for the given film
    {
        Console.WriteLine("'nAccess denied - you are too young");
    }
    else
    {
        Console.WriteLine("'nPlease call our office at 888-999-2928 to reserve tickets.");
    }
    Console.Read();
}

你可以考虑以下重构:

  static class Cinema
    {
        static void Main()
        {
            string[] titles = new string[] {"Rush", "How I Live Now", "Thor: The Dark World", "Filth", "Planes" };//array for the age requirements of each film
            int[] selection = new int[] { 15, 15, 12, 18, 0 };//array for the age requirements of each film
            int filmNumber; //parsed film number string 
            int age; //parsed age string
            Console.WriteLine("Welcome to our Multiplex.'n'nWe are presently showing:");
            for (int i = 0; i < titles.Length; i++)
            {
                Console.WriteLine("{0}. {1} ({2})",i+1, titles[i],selection[i]);
            }

            filmNumber = GetIntNumber(1, 5, "'nEnter the number of the film you wish to see: ", "'nPlease enter a number between 1 and 5: ");
            //loops as long as input is not an integer
            age = GetIntNumber(0, 125, "'nEnter your age: ", "'nPlease enter an age between 0 and 125: ") - 1; 
            if (age < selection[filmNumber-1]) //if too young for the given film
            {
                Console.WriteLine("'nAccess denied - you are too young");
            }
            else
            {
                Console.WriteLine("'nPlease call our office at 888-999-2928 to reserve tickets.");
            }
            Console.ReadLine();
        }
        static int GetIntNumber(int min, int max, string prompt, string inputPrompt)
        {
            int number;
            Console.Write(prompt);
            do  //loops as long as input is not between 1 and 5
            {
                Console.Write(inputPrompt);
                while (!int.TryParse(Console.ReadLine(), out number)) //loops as long as the input is not an integer
                {
                    Console.Write("'nYou must enter an integer number!");
                } 
            } while (number < min || number >max);
            return number;
        }

编辑选项1用于GetInNumber()方法提示处理:

    static int GetInNumber(int min, int max, string prompt, string inputPrompt)
    {
        int number;
        Console.Write(prompt);
        do  //loops as long as input is not between 1 and 5
        {
            while (!int.TryParse(Console.ReadLine(), out number)) //loops as long as the input is not an integer
            {
                Console.Write("'nYou must enter an integer number!: ");
            }
            if (number < min || number > max) Console.Write(inputPrompt); //<--| write input prompt if number out of range
        } while (number < min || number > max);
        return number;
    }