Question:
I am trying to create a program that will log HTML color schemes to a file, and I can’t get C++ to count in hex. I looked in the math header file and there aren’t any hex-specific commands. Or are there?
Answer:
One thing you need to be clear about is that all information stored in computer memory is binary. If you declare an integer for counting, those values will be stored as binary.
Hex is simply one of many ways to display a value as a string. So if you want to “count in hex,” use a binary data type, such as an integer, and then convert the integer to hex when you want to display it.
The main way you can convert a number to hex in C/C++ is using the very powerful sprintf
function.
int i;char s[50];i = 123;sprintf(s, “%04X”, i);cout << s;This code declares an integer and displays its value in hexadecimal format. The string “%04X” tells
sprintf
that you want the value displayed in hex format, that the result should be 4 characters long, and that leading characters should be displayed as zeros.