Question

进入＆＃39; q＆＃39;在第一个for循环期间（这应该会导致它断开.for循环仍打印出来＆＃34;请输入最多一千个值或输入'Q＆＃39;退出：＆＃34;。作为我我没有得到任何类型的编译器错误，我似乎无法弄清楚问题是什么。

unsigned int const size = 10;
StaticArray<int,size> arr;
int input;
for (int i = 0; i < size - 1; i++)
{
    cout << "Please enter up to one thousand values or enter 'Q' to exit: " << endl;
    cin >> input;
    cin.ignore(1000, 10);
    if (input == 'Q' || input == 'q')
        break;
    else
        arr.Push(input);
}

//output array
for (int i = 0; i < arr.getSize(); i++)
{
    cout << i << ". " << arr.Top() << endl;
    arr.Pop();
}

Answer 1

处理用户输入时，您必须更加小心处理输入，这可能包含预期值和意外值。这是让你入门的东西。

cin >> input;

// Check whether the number was successfully read.
if ( input.fail() )
{
   // The read could have failed due to reaching EOF
   // or by bad data. Check.
   if ( input.eof() )
   {
      // Do something sensible
   }
   else
   {
      // Clear the flags.
      input.clear();

      // Check whether the user entered Q or q
      char quit;
      input >> quit;
      if ( quit == `Q` || quit == `q` )
      {
         // Do the needful to quit.
      }
      else
      {
         // How do you want to handle the input if user entered 
         // something else...
      }
   }
}
else
{
   // The number was successfully read
   // Do the needful.
   // ...
}

适用于休息后的循环打印

1 个答案: