Friday, May 6, 2011

Is there a function that returns the ASCII value of a character? (C++)

I need a function that returns the ASCII value of a character, including spaces, tabs, newlines, etc...

On a similar note, what is the function that converts between hexadecimal, decimal, and binary numbers?

From stackoverflow
  • char c;
    int ascii = (int) c;
    

    A char is an integer, no need for conversion functions.

    Maybe you are looking for functions that display integers as a string - using hex, binary or decimal representations?

  • If you want to get the ASCII value of a character in your code, just put the character in quotes

    char c = 'a';
    
  • You don't need a function to get the ASCII value -- just convert to an integer by an (implicit) cast:

    int x = 'A';  // x = 65
    int y = '\t'; // x = 9
    

    To convert a number to hexadecimal or decimal, you can use any of the members of the printf family:

    char buffer[32];  // make sure this is big enough!
    sprintf(buffer, "%d", 12345);  // decimal: buffer is assigned "12345"
    sprintf(buffer, "%x", 12345);  // hex: buffer is assigned "3039"
    

    There is no built-in function to convert to binary; you'll have to roll your own.

  • You may be confusing internal representation with output. To see what value a character has:

    char c = 'A';
    cout << c << " has code " << int(c) << endl;
    

    Similarly fo hex valuwes - all numbers are hexadecimal numbers, so it's just a question of output:

    int n = 42;
    cout << n << " in hex is " << hex << n << endl;
    

    The "hex" in the output statement is a C++ manipulator. There are manipulators for hex and decimal (dec), but unfortunately not for binary.

  • As far as hex & binary - those are just representations of integers. What you probably want is something like printf("%d",n), and printf("%x",n) - the first prints the decimal, the second the hex version of the same number. Clarify what you are trying to do -

0 comments:

Post a Comment