Question

我在C＃中使用#include <codecvt> #include <locale> #include <cassert> template<class F> struct myFacet : F { using F::F; ~myFacet() {} }; int main() { std::string in = u8"水"; // UTF-8 // utf8 to wide (could've used en_US.utf8, but this one exists as-is) std::wstring ws = std::wstring_convert<std::codecvt_utf8<wchar_t>>{}.from_bytes(in); assert(ws == L"水"); // wide to another mb (have to use a named locale now) typedef myFacet<std::codecvt_byname<wchar_t, char, std::mbstate_t>> F; std::string out = std::wstring_convert<F>{ new F("zh_CN.gb18030") }.to_bytes(ws); assert(out == "\xcb\xae"); }来计算不同形状的区域。以下是我的代码：

enums

以下内容会产生错误：

using System;
class Area
{
    public enum Shape{Circle,Square};
    public void AreaShape(int x,Shape ob1)
    {
        double a;
        switch(x)
        {
            case (int)Shape.Circle:
                a=Math.PI*x*x;
                Console.WriteLine("Circle "+a);
                break;
            case (int)Shape.Square:
                a=x*x;
                Console.WriteLine("Square "+a);
                break;
            default:
                Console.WriteLine("Invalid");
                break;
        }
    }
}
class MyTestOne
{
    public static void Main(String[] a)
    {
        Area obj1=new Area();
        obj1.AreaShape(15,Area.Shape.Circle);
        obj1.AreaShape(15,Area.Shape.Square);
    }
}

如何获得以下输出？

obj1.AreaShape(15,Shape.Circle);
obj1.AreaShape(15,Shape.Square);

当我使用Circle 225*pi Square 225和Area.Shape.Circle时，输出为：

Area.Shape.Square

Answer 1

传递形状枚举类而不是int x变量

            switch (ob1)
            {
                case Shape.Circle:
                    a = Math.PI * x * x;
                    Console.WriteLine("Circle " + a);
                    break;
                case Shape.Square:
                    a = x * x;
                    Console.WriteLine("Square " + a);
                    break;
                default:
                    Console.WriteLine("Invalid");
                    break;
            }

Answer 2

您的switch语句会启用x，您始终将其作为15传入。你应该打开ob1枚举变量，你不需要演员。

C＃ - 输出无效

2 个答案: