C++字符测试；输入特定字母后如何使程序正常结束？

Question

实验室专注于测试角色。我应该输入一个字符，如果它是大写字母、小写字母或其他类型，它将读取。我的 if 语句是正确的。我的提示和阅读我输入内容的语句也可以。问题是当我输入应该使程序结束的 q 或 Q 时，程序仍然读取我输入的 q 或 Q。程序不应该在我输入后结束并且不阅读那些字母吗？

 int main()
    {
        char input = ' ';

        //set up loop such that all tasks below is done as long as input
        // is not a q or a Q (that is, quit)
        while (toupper(input) != 'Q' || tolower(input) != 'q') 
        {
            cout << "Enter any character: ";
            cin.get(input);
            cin.ignore(); 
            cout << "The character you entered is: " << input << endl;

            if (isalpha(input))
                cout << "That's an alphabetic character.\n";
            if (isdigit(input))
                cout << "That's a numeric digit.\n";
            if (islower(input))
                cout << "The letter you entered is lowercase.\n";
            if (isupper(input))
                cout << "The letter you entered is uppercase.\n";
            if (isspace(input))
                cout << "That's a whitespace character.\n";

            //add code to test for alphanumeric 
            if (isalnum(input))
                cout << "The character you entered is alphanumeric.\n"; 

            //add code for a punctuation
            if (ispunct(input))
                cout << "The character you entered is a punctuation.\n";
        } 

        system("PAUSE"); 
        return 0;
    }

Answer 1

删除 system("PAUSE"); 并重试。

使用“q”或“Q”退出 while 循环后，程序/控制台仍坐在那里等待输入/输出。