how do you represent the arrow keys in c++

Are they represented by numbers or words or what?

key = getch();
switch(key){
case 'K': //left arrow

case 'M': //right arrow

case 'H': //up arrow

case 'P': //down arrow
}

This should work. Remember to #include stdlib.h(I think that's right) for getch().

I ment the arrow keys on a keyboard not letters!

Standard representation for GREY arrow keys:

UP: 48h (72)
LEFT: 4Bh (75)
RIGHT: 4Dh (77)
DOWN: 50h (80)

As for MSVC++, I don't know how to trap non-alphanumeric
keypresses other than the ENTER key ('\n'). One way to overcome
this would be to use inline assembly to create your own input
loop with the following instructions:

xor ax,ax ;Function #0: await a user keypress
int 16h ;Wait for a keypress: store in AX

The above keycodes would then be stored in the AH register.
They should be the same with the MS compiler, but again, I do not
know whether or not it is possible to trap them with the get()
function alone.

For more info. on inline ASM, please visit http://msdn.microsoft.com -> Search -> 'Inline Assembly'

Regards,
Peter Kimberley
[email protected]

Flikm is correct.

If you look at your ascii code charts the values kimberleyp gave equate to Flikm's statement.

UP: 48h (72) = 'H'
LEFT: 4Bh (75) = 'K'
RIGHT: 4Dh (77) = 'M'
DOWN: 50h (80) = 'P'


To make sure I wrote a program from Flikm's outline.

When reading a function key or an arrow key, _getch (no echo) and _getche (echoes) must be called twice; the first call returns 0 (function key) or 0xE0 (arrow key), and the second call returns the actual key code. Don't know why but it was documented that way in MSDN.

Code:

---

#include "stdafx.h"
#include <conio.h>
#include <iostream>
using namespace std;

int main ()
{
        char key = _getch();
        if( ( key == static_cast<char>( 0xe0 ) )|| ( key == static_cast<char>( 0x00 ) ) )
        {
                key = _getch();
        }
       
        switch(key)
        {
                case 'K': //left arrow
                        {
                                cout << "left arrow " << endl;
                                break;
                        }

                case 'M': //right arrow
                        {
                                cout << "right arrow " << endl;
                                break;
                        }
       
                case 'H': //up arrow
                        {
                                cout << "up arrow " << endl;
                                break;
                        }

                case 'P': //down arrow
                        {
                                cout << "down arrow " << endl;
                                break;
                        }
                default :
                        {
                                cout << "Not an arrow" << endl;
                                break;
                        }
        }

        return 0;
}

---

Thanks! :D