C# 在 switch 语句中没有隐式失败

Question

我来自 C++ 背景。我最近写了一个程序，提供有关特定 Rs 的音符数量的信息。当它要求特定数量时需要。下面是我的代码：

#include <iostream>
using std::cout;
using std::cin;
int main()
{
    int amount,notes,choice;
    cout<<"Enter the amount: ";
    cin>>amount;
    cout<<"Enter the value of note from which you want to start: ";
    cin>>choice;
    switch(choice)
    {
        case 100:
            notes=amount/100;
            cout<<"no of 100 rupees notes = "<<notes<<'\n';
            amount=amount%100;
        case 50:
            notes=amount/50;
            cout<<"no of 50 rupees notes = "<<notes<<'\n';
            amount=amount%50;
        case 20:
            notes=amount/20;
            cout<<"no of 20 rupees notes = "<<notes<<'\n';
            amount=amount%20;
        case 10:
            notes=amount/10;
            cout<<"no of 10 rupees notes = "<<notes<<'\n';
            amount=amount%10;
        case 5:
            notes=amount/5;
            cout<<"no of 5 rupees notes = "<<notes<<'\n';   
            amount=amount%5;
        case 2:
            notes=amount/2;
            cout<<"no of 2 rupees notes = "<<notes<<'\n';
            amount=amount%2;
        case 1:
            notes=amount/1;
            cout<<"no of 1 rupees notes = "<<notes<<'\n';
            break;
        default:
            cout<<"Enter only valid values";
    }
    return 0;
}

现在我的问题是如何用 C# 编写这个程序？在 C# 中没有隐式掉落案例，但在这个程序中需要隐式掉落案例。那么我可以通过哪些方式在 C# 中执行此程序？请帮助我。

Answer 1

原因是隐式失败是导致细微错误的原因，当您忘记添加时 break; 如果需要失败，可以使用 goto:

case 100:
    notes=amount/100;
    cout<<"no of 100 rupees notes = "<<notes<<'\n';
    amount=amount%100;
    goto case 50;

Answer 2

就我个人而言，我倾向于采用完全不同的方法。通过数组而不是开关。

类似于：

using System;

namespace Test
{
    class MainClass
    {
        public static void Main (string[] args)
        {
            int[] notes = new int[] { 100, 50, 20, 10, 5, 2, 1 };
            int amount = 0;

            amount = Convert.ToInt32 (Console.ReadLine ());
            foreach (int i in notes) {
                Console.WriteLine (amount / i);
                amount = amount % i;
            }
        }
    }
}

Answer 3

Dennis_E 对您来说是最简单的更改，但您可以通过使用循环结构来避免 goto 和大量重复:)

例如：

using System;

namespace CurrencyNotes
{
    class Program
    {
        static void Main(string[] args)
        {
            int amount;
            int choice;

            Console.Write("Enter the amount: ");
            amount = Convert.ToInt32(Console.ReadLine());

            Console.Write("Enter the value of note from which you want to start: ");
            choice = Convert.ToInt32(Console.ReadLine());

            CountNotes(amount, choice);
        }

        static void CountNotes(int amount, int choice)
        {
            int notes = 0;
            int[] choices = { 100, 50, 20, 10, 5, 2, 1 };

            // Find starting choice
            int i = 0;
            while (choice < choices[i])
                ++i;

            // Output number of notes for each suitable choice
            while (amount > 0)
            {
                notes = amount / choices[i];
                if (notes > 0)
                    Console.WriteLine("no. of {0} rupees notes = {1}", choices[i], notes);
                amount %= choices[i];
                ++i;
            }
        }
    }
}

C# 在 switch 语句中没有隐式失败

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