很简单。 枚举是从0开始的数字的占位符/单词。 就是这样。 您可以键入stop-而不是0，这使代码更具可读性。 您也可以将它与字符串和其他东西进行比较，但对于一开始来说，它只是这样。 我给你写了一个输入数字的简单代码:

#include <iostream>
#include <limits> //numeric_limits, streamsize...

using std::cin, std::cout, std::endl; //Don't specify the whole namespace, just the few you need

enum gameOver{STOP/* or 0*/, LEFT/* or 1*/, RIGHT/* or 2*/, UP/*or 3*/, DOWN/*or 4*/, EXIT/*or 5*/};


int main()
{
    int input{}; //c++17 declaration - equals input = 0;


      while(true){ //running forever until return 0
          cout << "Type a number:\n" << endl;

          while(!(cin >> input) || cin.bad()){  //check the Input format for integer the right way
                cin.clear();
                cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
                cout << "Invalid input.  Try again: ";
              }

      switch (input) {
      case STOP: //equals number 0
          cout << "stop" << STOP << endl;
          break;
      case LEFT: //equals number 1
          cout << "left" << LEFT << endl;
          break;
      case RIGHT: //equals number 2
          cout << "right" << RIGHT << endl;
          break;
      case 3: //or just a number - equals UP
          cout << "up" << UP << endl;
          break;
      case DOWN: //equals number 4
          cout << "down" << DOWN <<endl;
          break;
      case EXIT: //equals number 5
          cout << "exit" << EXIT << endl;
          return 0;
      default:
          cout << "wrong input" << endl;
          break;
      }

    }
}

如果您编写了几行以上的示例代码，只需使用using std::cin或what指定您出于各种原因正在使用的代码。

还要始终检查输入是否有效。 我为您添加了一些简单的验证循环。

我用第二个枚举展开了它。 通常，您在include指令下声明它，但在函数之前声明它，以使em对整个程序计算，编译器可以将em放入。

#include <iostream>
#include <limits> //numeric_limits, streamsize...

using std::cin, std::cout, std::endl; //Don't specify the whole namespace, just the few you need

enum gameOver{STOP/* or 0*/, LEFT/* or 1*/, RIGHT/* or 2*/, UP/*or 3*/, DOWN/*or 4*/, EXIT/*or 5*/};
//you can also specify different enums. They still equals always the same numbers
enum selection{ZERO/* or 0*/, ONE/* or 1*/, TWO/* or 2*/};


int main()
{
    int input{};


      while(true){
          cout << "Type a number:\n" << endl;

          while(!(cin >> input) || cin.bad()){  //check the Input format for integer the right way
                cin.clear();
                cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
                cout << "Invalid input.  Try again: ";
              }

      switch (input) {
          //you can call em like a class
      case gameOver::STOP: //equals number 0
          cout << "stop" << STOP << endl;
          break;
      case selection::ONE: //equals number 1
          cout << "left" << LEFT << endl;
          break;
          //or like this for simple programs
      case TWO: //equals number 2
          cout << "right" << RIGHT << endl;
          break;
      case 3: //or just a number - equals UP
          cout << "up" << UP << endl;
          break;
      case DOWN: //equals number 4
          cout << "down" << DOWN <<endl;
          break;
      case EXIT: //equals number 5
          cout << "exit" << EXIT << endl;
          return 0;
      default:
          cout << "wrong input" << endl;
          break;
      }

    }
}