C# do while 循环 - 如何记住用户输入？

Question

我是 C# 新手，我正在编写一个 do while 循环，该循环继续要求用户输入“价格”，直到他们输入“-1”作为价格。

之后，我需要将他们输入的所有价格值相加，并将其声明为小计。

我遇到的问题是它只记住最后输入的数字，即 -1。 我该怎么做才能解决这个问题？

using System;

namespace ConsoleApp1
{
class Program
{
    static void Main()
    {
        Console.WriteLine("Your Receipt");
        Console.WriteLine("");
        Console.WriteLine("");

        decimal count;
        decimal price;
        decimal subtotal;
        decimal tax;
        decimal total;

        count = 1;

        do
        {
            Console.Write("Item {0} Enter Price: ", count);
            ++count;
            price = Convert.ToDecimal(Console.ReadLine());


        } while (price != -1);

        subtotal = Convert.ToInt32(price);
        Console.Write("Subtotal: ${0}", subtotal);

    }
}

}

Answer 1

尝试对 Artem 的答案进行这种变体。 我认为这更清洁一些。

int count = 0;
decimal input = 0;
decimal price = 0;

while (true)
{
    Console.Write("Item {0} Enter Price: ", count++);
    input = Convert.ToDecimal(Console.ReadLine());
    if (input == -1)
    {
        break;
    }
    price += input;
}

Answer 2

使用列表并不断将条目添加到列表中。 或者您可以将运行总数保留为另一个整数。

就像是：

int total = 0; // declare this before your loop / logic other wise it will keep getting reset to 0.
total = total+ input;

Answer 3

在循环的每次迭代中，您都会覆盖price的值。 单独的输入和存储price 。

decimal input = 0;

do
{
    Console.Write("Item {0} Enter Price: ", count);
    ++count;
    input = Convert.ToDecimal(Console.ReadLine());
    if (input != -1)
        price += input;
} while (input != -1);

Answer 4

请尝试使用这个

using System;

namespace ConsoleApp1
{
class Program
{
    static void Main()
    {
        Console.WriteLine("Your Receipt");
        Console.WriteLine("");
        Console.WriteLine("");

        decimal count;
        decimal price;
        decimal subtotal = 0m; //subtotal is needed to be initialized from 0
        decimal tax;
        decimal total;

        count = 1;

        do
        {
            Console.Write("Item {0} Enter Price: ", count);
            ++count;
            price = Convert.ToDecimal(Console.ReadLine());
            if (price != -1)  //if the console input -1 then we dont want to make addition
              subtotal += price; 

        } while (price != -1);

        //subtotal = Convert.ToInt32(price); this line is needed to be deleted. Sorry I didnt see that.
        Console.Write("Subtotal: ${0}", subtotal); //now subtotal will print running total

    }
}
}