Thread: problem with getch()

I think you mean that you don't want them to have to press enter after typing the age variable in? It can be done...but with the logic available, it's not optimal....basically you could do this

Code:

using namespace std;
...

int max=2;//this allows the age to be 10-99 years
std::cin.get(age,max);

//or

int max=3;//allows to be 100-999
std::cin.get(age,max);

note: it is possible to get any age up to max (so for max=2 you could be 0-9 years old, but they'd have to press the enter key.


If i'm answering a question besides the one you asked ...then could you be more specific as to what you want?

DarkKinG,

Code:

#include <iostream>
#include <conio.h>

int main()
{
  int age;
  std::cout << "Please enter your age here -> ";
  std::cin >> age;
  if (age > 100)
	  {
		  std::cout << "Your pretty old are'nt u ! lol";
	  }
  else if (age == 100)
	  {
		  std::cout << "So you got 100 years old .. haha";
	  }
  else
	  {
		  std::cout << "Your pretty young :P";
	  }
  getch();
  return 0;
}

This code executes perfectly well, both on Borland and MSVC++6.. (Your "smilies" don't work, but...)

-Skipper

cin and getch() don't go together. Use fgets() and getch(), no problem.

Sebastiani,

'fgets()'?

Are you trying to send this entire Board into a 'tailspin'?

You don't presume to think that C++ people know about 'fgets()', do you?

You're right. getch() is non-Standard, as is <conio>. (Not an insurmountable problem, but ...)

The code presented is fine, "as is". (Ran it myself.That'll make you sleep better tonight!! )

Ever notice that the "poster" catches" up much later than the rest of us?

Understandable, I'm sure. They're coding and we're goofing off!

-Skipper

Use fgets() in both C & C++, otherwise overload cin. Why? Because it can cause unexpected tailspins of it's own, such as passing multiple inputs, newline insertions, etc.
If you wish to use cin >> then beware of it's idiosyncrocies, that's all.

Originally posted by Unreg1stered


How about include <stdlib.h> and use system("Pause"); instead of using getch()? (assuming that your code is to run under Dos/Windows)

system() calls are slow, very very platform dependant

you can do this:

Code:

std::cin>>age;
std::cin.clear()://clears the input buffer so it will not conflict with getch()
...
getch()

it will run fine.

My understanding of std::cin.clear(); is that this command "clears" error bits, i.e. resets the input stream error flags. (Wish someone would clarify this one, once and for all. )

One surprisingly simple method of flushing the stream is to use 'std::endl;' which does the trick. (Also surprising how few of us remember this little goodie, me included.)

(MSVC++, for one, has a problem with the istream buffer and getch();, so it behooves folks using that compiler to recognize this shortcoming. Relying exclusively on Borland, this gave me fits for a time.)

-Skipper

it is my understanding that std::cin.clear() clears EVERYTHING from the input buffer. I've also been told that cin.flush() does similar, but is used differently as far as syntax goes. Another trick of the trade, besides std::endl; is to do something like this:

Code:

std::cin>>age,cin.get();

basically, the return key signals the input of a varialble, but the '\n' code is not included in the variable, so it sits in the input buffer. If you have getch() or sometimes even another cin (depends on the quirkieness of the compiler ie: MSVC++) it will read the input buffer, see the '\n' and believe that what you've typed (which is nothing) has been completed so it almost seamlessly skips over that little section of code. IE:

Code:

cin>>age;
cin>>something;
cout<<age<<'\n'<<something;
//would ask for age, then seem to skip over asking for something