我建议你改变一些东西在这里。你熟悉面向对象的设计吗?如果不是的话,强烈建议你阅读一下,如果你想用C++编写代码(或者只是编写代码,因为它是许多编程语言的主要方面)
考虑处理每个菜单和子菜单作为单独的对象。每次进入循环时,使用对象指针调用打印当前菜单文本的方法。
然后,按正常方式接受用户的输入,然后更改您现在使用的菜单对象。
这可能不是执行控制台菜单的最理想方式,但它会为您提供面向对象编程的强大基础。
我装戴例子:
#include <iostream>
#include <string>
class BaseMenu
{
public:
BaseMenu() { m_MenuText = "This shouldn't ever be shown!"; } // This is the constructor - we use it to set class-specific information. Here, each menu object has its own menu text.
virtual ~BaseMenu() { } // This is the virtual destructor. It must be made virtual, else you get memory leaks - it's not a quick explaination, I recommend you read up on it
virtual BaseMenu *getNextMenu(int iChoice, bool& iIsQuitOptionSelected) = 0; // This is a 'pure virtual method', as shown by the "= 0". It means it doesn't do anything. It's used to set up the framework
virtual void printText() // This is made virtual, but doesn't *have* to be redefined. In the current code I have written, it is not redefined as we store the menu text as a string in the object
{
std::cout << m_MenuText << std::endl;
}
protected:
std::string m_MenuText; // This string will be shared by all children (i.e. derived) classes
};
class FirstMenu : public BaseMenu // We're saying that this FirstMenu class is a type of BaseMenu
{
FirstMenu()
{
m_MenuText = "Main Menu\n" // What we are doing here is setting up the string to be displayed later
+ "Please make your selection\n" // What we are doing here is setting up the string to be displayed later
+ "1 - Start game\n" // What we are doing here is setting up the string to be displayed later
+ "2 - Options\n" // What we are doing here is setting up the string to be displayed later
+ "3 - Quit\n" // What we are doing here is setting up the string to be displayed later
+ "Selection: "; // What we are doing here is setting up the string to be displayed later
}
BaseMenu *getNextMenu(int choice, bool& iIsQuitOptionSelected) // This is us actually defining the pure virtual method above
{
BaseMenu *aNewMenu = 0; // We're setting up the pointer here, but makin sure it's null (0)
switch (choice) // Notice - I have only done "options". You would obviously need to do this for all of your menus
{
case 2:
{
aNewMenu = new SecondMenu; // We're creating our new menu object here, and will send it back to the main function below
}
case 3:
{
// Ah, they selected quit! Update the bool we got as input
iIsQuitOptionSelected = true;
}
default:
{
// Do nothing - we won't change the menu
}
}
return aNewMenu; // Sending it back to the main function
}
};
class SecondMenu : public BaseMenu
{
SecondMenu()
{
m_MenuText = "OptionsMenu\n"
+ "Please make your selection\n"
+ "1 - ????"
+ "2 - dafuq?";
}
BaseMenu *getNextMenu(int choice, bool& iIsQuitOptionSelected) // This is us actually defining the pure virtual method above
{
BaseMenu *aNewMenu = 0; // We're setting up the pointer here, but makin sure it's null (0)
switch (choice) // Notice - I have only done options. You would obviously need to do this for all of your menus
{
case 1:
{
aNewMenu = new FirstMenu; // We're creating our new menu object here, and will send it back to the main function below
}
break;
case 2:
{
aNewMenu = new FirstMenu; // We're creating our new menu object here, and will send it back to the main function below
}
break;
default:
{
// Do nothing - we won't change the menu
}
}
return aNewMenu; // Sending it back to the main function
}
};
int main (int argc, char **argv)
{
BaseMenu* aCurrentMenu = new FirstMenu; // We have a pointer to our menu. We're using a pointer so we can change the menu seamlessly.
bool isQuitOptionSelected = false;
while (!isQuitOptionSelected) // We're saying that, as long as the quit option wasn't selected, we keep running
{
aCurrentMenu.printText(); // This will call the method of whichever MenuObject we're using, and print the text we want to display
int choice = 0; // Always initialise variables, unless you're 100% sure you don't want to.
cin >> choice;
BaseMenu* aNewMenuPointer = aBaseMenu.getNextMenu(choice, isQuitOptionSelected); // This will return a new object, of the type of the new menu we want. Also checks if quit was selected
if (aNewMenuPointer) // This is why we set the pointer to 0 when we were creating the new menu - if it's 0, we didn't create a new menu, so we will stick with the old one
{
delete aCurrentMenu; // We're doing this to clean up the old menu, and not leak memory.
aCurrentMenu = aNewMenuPointer; // We're updating the 'current menu' with the new menu we just created
}
}
return true;
}
注意,这可能是开始了一个有点复杂。我强烈建议您阅读人们已发布的其他答案。它应该给你一些关于如何去做的方法,你可以从基础到更复杂的过程,检查每一个变化。
这大致产生了我的问题。 除了回到主菜单外,你可以正确地工作。这只是不会发生。 – fanatical
好的,我已经测试了我的代码,并对选择变量做了一些小改进,它应该在do-while循环之外声明(我相应地更新了我的帖子中的代码)。但除了这个小缺陷之外,它对我来说非常合适。 –