Detecting ASCII???

[mr_cheeks]

detecting ASCII???
I have created a file and have populated it with names and their gender (male or female). Gender can either be inputted as a M or as an F by the user....If the user enters anything else, an error message should appear.
I initially tried this:

if( ( gender == "m" ) || ( gender == "m") )
{
then write to file
}


but the file did not accept any input.

I then tried this

if( ( gender == '10101001' ) || ( gender == '10100010' ) )
taking the ASCII code for m and f but I got a compile error (i beleive since i defined gender to be of char type).

How do i code : do not accept any other letters for gender besides M,m,F or f (case sensitive???).

THANK YOU.

[madhu]

char should be compared with single quotes like this:

if( ( gender == 'm' ) || ( gender == 'M') )

[Justin]

Code: Select all

if( ( gender == '10101001' ) || ( gender == '10100010' ) )


That's not ASCII, it's binary. In fact, it's not even binary, it's a literal since you have it in quotes, in fact! it's a compiler error because you have a literal of more than one character in single quotes when it should be double quotes. According to VC++ 6.0, it is "error C2015: too many characters in constant."

Anyway, if you want to compare ASCII values, you need to do the following.

+Get an ASCII reference table (here's one http://gha.kicks-ass.org/archive/Ascii_ ... _codes.png )
+Typecast your char, gender, to an int and compare that to the ASCII value of whatever you're looking for.

Try something like this:

Code: Select all

if (int(gender) == 77 || int(gender) == 109 ||  // 'M' and 'm'
  int(gender) == 70 || int(gender) == 102) {  // 'F' and 'f'
  // Do something neat
}

Technically, you don't have to explicitly typecast the char variable, but sometimes it's nice so that you can remember what you're doing, especially when you're new.

[omnius]

Code: Select all

if (int(gender) == 77 || int(gender) == 109 ||  // 'M' and 'm'
  int(gender) == 70 || int(gender) == 102) {  // 'F' and 'f'
  // Do something neat
}

Ugghhh! 'M' and 'm' are so much more readable than 77 and 109, and remove the need for the comment. ;-)

[Justin]

I completely agree, I thought that's what he wanted to do though, since he was coming out with the binary and all