輸入驗證迴路用繩子

Question

我剛學C++（1周的經驗），並嘗試寫一個輸入驗證循環，要求用戶輸入「是」或「否」。我想通了，但有一種感覺，有一個更好的方法來解決這個問題。這是我想出了：

{ 
    char temp[5]; // to store the input in a string 
    int test; // to be tested in the while loop 

    cout << "Yes or No\n"; 
    cin.getline(temp, 5); 

    if (!(strcmp(temp, "Yes")) || !(strcmp(temp, "No"))) // checks the string if says Yes or No 
     cout << "Acceptable input";       // displays if string is indeed Yes or No 
    else             //if not, intiate input validation loop 
    { 
     test = 0; 
     while (test == 0) // loop 
     { 
      cout << "Invalid, try again.\n"; 
      cin.getline(temp, 5);    // attempts to get Yes or No again 
      if (!(strcmp(temp, "Yes")) || !(strcmp(temp, "No"))) // checks the string if says Yes or No 
       test = 1;   // changes test to 1 so that the loop is canceled 
      else test = 0;  // keeps test at 0 so that the loop iterates and ask for a valid input again 
     } 
     cout << "Acceptable input"; 
    } 

    cin.ignore(); 
    cin.get(); 

    return 0; 
} 

我爲我的可憐的筆記道歉，不知道什麼是相關的。我也使用cstring頭。

Answer 1

我想你想一個do while循環：

bool test = false; 
do 
{ 
    cout << "Yes or No\n"; 
    cin.getline(temp, 5); 
    if (!(strcmp(temp, "Yes")) || !(strcmp(temp, "No"))) // checks the string if says Yes or No 
    { 
     cout << "Acceptable input"; // displays if string is indeed Yes or No 
     test = true; 
    } 
    else 
    { 
     cout << "Invalid, try again.\n"; 
    } 

} while (!test); 

Answer 2

更妙的是IMO：

std::string answer; 

for(;;) { 
    std::cout << "Please, type Yes or No\n"; 
    getline(std::cin, answer); 

    if (answer == "Yes" || answer == "No") break; 
} 

您也可以將答案爲，允許用戶鍵入不僅是「是」低的情況下，而且「是」，「是的」，等等。參見this question