Enter to Continue, Esc to leave

[julianenepom]

Hi there. Im having this:

printf("Press Enter to continue or Esc to leave the program.");

Now, if the user press "Enter" the program starts again from the begining. If the Escape key is pressed, just quit the program.

Any tips?

Thx
July

[cas]

I presume you want to be able to read a key without the user having to hit enter first. That's not possible in standard C. Check the FAQ, a couple of system-specific methods are covered.

[julianenepom]

I dont know If anyone got it, but its a program to change Celsius to Fahrenheit.

main(){
       float var, opc;
       
       printf("Type the value:");
       scanf("%f", &var);
       
       printf("\n(1)Celsius to Fahrenheit\n(2)Fahrenheit to Celsius\n\nType your number:");
       scanf("%f", &opc);
       
       if (opc == 1)
          {
          var = var * 9 / 5;
          var = var + 32;
          }
              
       if (opc == 2)
          {
          var = var - 32;
          var = var * 5 / 9;
          }
       
         
       printf("%.1f", var);  
       system ("pause > null");

       printf("Press Enter to continue or Esc to leave the program.");

       }

Pressing Enter will start the program again... =P

[cpjust]

Here's the first result I found in Google: Getch() Esc Key - C And C++ | Dream.In.Code

[julianenepom]

I need something like, "Press Enter do start the program again".
What do I need to do?

[julianenepom]

#include <stdio.h>
#include <stdlib.h>

int calc()
{
  
    float var, opc;
    int cmd;
    cmd = 0;
    
    printf("Type the temperature: ");
    scanf("%f", &var);
    
    printf("\n(1)Celsius to Fahrenheit\n(2)Fahrenheit to Celsius\n\nType here: ");
    scanf("%f", &opc);
    
    if (opc == 1)
      {
      var = var * 9 / 5;
      var = var + 32;
      }
          
    if (opc == 2)
      {
      var = var - 32;
      var = var * 5 / 9;
      }
    
    printf("%.1f", var);  
    system ("pause > null");
    return 0;
   
}

int main()
{

calc();

}

Now I just need to keep restarting it over and over, till esc is pressed.

Thx. =)

[cpjust]

Have you learned how to use while loops yet?

[julianenepom]

I used the do/while, and its ok now. thx for the help
For anyone how ever needs it, here is the code:

/* Celsius to Fahrenheit and vice-versa */

#include <stdio.h>
#include <stdlib.h>

main()
{
  
    float var, opc;
    int c;
    
    do{

        printf("Type the value: ");
        scanf("%f", &var);
        
        printf("\n(1)Celsius to Fahrenheit\n(2)Fahrenheit to Celsius\n\nOption: ");
        scanf("%f", &opc);
        
        if (opc == 1)
          {
          var = var * 9 / 5;
          var = var + 32;
          }
              
        if (opc == 2)
          {
          var = var - 32;
          var = var * 5 / 9;
          }
        
        printf("%.1f\n\n", var);
        printf("Type 1 to continue or 0 to exit: ");
        scanf("%d", &c);
        system ("cls");

    }while (c != 0);
}

[cpjust]

system ("cls");

That'll only work on DOS/Windows though.
On UNIX it's "clear" instead of "cls".
If your teacher tries running it on a different OS, it won't clear the screen and say that it doesn't know what "cls" is.

One way to make it work on any OS is to just print about 50 '\n' characters instead of clearing the screen (although it won't look at nice, since you can just scroll up in the command window and see all the previous output).

[Salem]

Or just note that almost all actual command line tools (with the possible exception of the "more"-like tools) don´t bother with clearing the screen at all.