wait_yn.c

不错书对C++/C程序员很有用的大家不要错过.

#include <stdio.h>
#include <ctype.h>
#include <conio.h>

void main(void)
 {
   char letter;  												 // Letter typed by the user

   printf("Do you want to continue? (Y/N): ");

   letter = getch();         								 // Get the letter
   letter = toupper(letter);  							 // Convert letter to uppercase
   
   while ((letter != 'Y') && (letter != 'N'))
     {
       putch(7);      			      			      // Beep the speaker
       letter = getch();      			 			   // Get the letter
       letter = toupper(letter);						   // Convert letter to uppercase
     }

   printf("\nYour response was %c\n", letter);
 }