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How do I get the scanf to accept a RETURN as the Default choice switch.

I have a program that uses switch ie.

Enter 1 for this
Enter 2 for this
Enter 3 for this

How do I get the scanf to accept a RETURN as the choice?

Enter return for choice 4.

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scuzz1
Asked:
scuzz1
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1 Solution
 
ankuratvbCommented:
Do this:

int main()
{
 char c;
 scanf("%c",&c);
 //when return is pressed c='\n';
 switch(c)
 {
  case '1':break;
  case '\n':break;
 }
}
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scuzz1Author Commented:
Is there a way I can do this so it dosn't accept char's?
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ankuratvbCommented:
Try this:

int main()
{
int c;
scanf("%c",&c);
//when return is pressed c=10;
c=c-48;//if return c=-38;
switch(c)
{
 case 1:break;
 case -38:break;
}
}
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ankuratvbCommented:
U can do this as well:

Similar to last one.Just explains scanf options:

int main()
{
int c=0;
scanf("%[^\n]",&c);//accept input till enter is not pressed
//when return is pressed c=0 the initial value; else ascii for digit is returned
c=c-48;//if return c=-48;
switch(c)
{
case 1:break;
case -48:break;
}
}
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Avik DasguptaCommented:
Hi, u can scanf ur input as a character
scanf("%c",&c);

switch (c)
{
...
case '\r' : for return key
}

Avik.
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Avik DasguptaCommented:
sorry, make that '\n'. Although previously answered.

Avik.
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Avik DasguptaCommented:
Hi,
Another suggestion as u said ...
>> Is there a way I can do this so it dosn't accept char's?

It is not possible to examine a 'return' entry without accepting the entry as a character.
Ankuratvb 's suggestions are somehow not working in my compiler(Turbo C++ v3.0). i.e it is not accepting c=10 when the 'ENTER' key is pressed. U can try to get the ascii of a number by interrupt calling. (Remember all these fuss would not have been done if u wanted the normal way).
THIS ROUTINE IS ONLY APPLICABLE IN DOS ENV.
// example code not pertaining to ur problem
#include<stdio.h>
#include<dos.h>
void main()
{
 int c;
 union REGS r;
 int86(0x16,&r,&r); // interrupt call
 c=r.h.al; // contains the ascii code
 switch(c){
  case 13:{ printf("1");break;}// 'return key pressed'
  default : printf("0");
 }
 getch();
}
The ascii of 'return key' is 13.
Instead of writing the scanf statement call the inturrupt statement int86(0x16,&r,&r). here 0x16 is the inturrupt number which is generally multiplied by 4 to get to the interrupt service routine. Here the ISR is the scan keyboard one and it outputs the ascii value scanned in the lower half of 16 bit register A(it considers 16 bit portion in DOS).

Avik.
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Avik DasguptaCommented:
Ohhhh. if i do int c=getchar() and press return i get c=10 but when c=getch() is done 13 is returned, i think it to be the \r\n combination that is causing the problem. i.e
\r is returned by getch() which is the return key
\n (next character) is returned by getchar() which is the newline key.

so to avoid all the ROM BIOS interrupt techniques u can just do
c=getch();

Avik.
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scuzz1Author Commented:
This worked.

I just did a cast to int to get the ascii or the return which is 10.

thanks.
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