C#控制台输出格式

Question

我试图得到一个因子显示为例如(5的阶乘是5*4*3*2*1)

我正在使用factorial的方法,但它不接受Console.Write(i + " x ");我的代码中的行.

任何帮助都会很棒.这是我的代码.

//this method asks the user to enter a number and returns the factorial of that number
static double Factorial()
{
    string number_str;
    double factorial = 1;

    Console.WriteLine("Please enter number");
    number_str = Console.ReadLine();

    int num = Convert.ToInt32(number_str);

    // If statement is used so when the user inputs 0, INVALID is outputed
    if (num <= 0)
    {
        Console.WriteLine("You have entered an invalid option");
        Console.WriteLine("Please enter a number");
        number_str = Console.ReadLine();

        num = Convert.ToInt32(number_str);
        //Console.Clear();
        //topmenu();
        //number_str = Console.ReadLine();
    }

    if (num >= 0)
    {
        while (num != 0) 
        {
            for (int i = num; i >= 1; i--)
            {
                factorial = factorial * i;
            }
            Console.Write(i + " x ");

            Console.Clear();
            Console.WriteLine("factorial of " + number_str.ToString() + " is " + factorial);
            factorial = 1;
            Console.WriteLine("(please any key to return to main menu)");
            Console.ReadKey();
            Console.Clear();
            topmenu();
        }
    }

    return factorial;
}

谢谢!

Answer 1

问题是你的for循环没有使用大括号,所以范围只是一行.

尝试适当添加大括号:

for (int i = num; i >= 1; i--)
{
    factorial = factorial * i;
    Console.Write(i.ToString() + " x ");
}

Console.WriteLine("factorial of " + number_str.ToString() + " is " + factorial);    

如果没有大括号,i变量只存在于下一个语句(factorial = factorial * i;)中,并且在您调用时不再存在于作用域中Console.Write.

你可能还想删除Console.Clear紧随其后的电话Write,否则你将看不到它.