Thread: Converting a hex string to hex

Hi, I'm trying to write a function to decode HTML encoded ASCII. I was just wondering if there is an easy method to convert a hex value in a string to a hex value.

i.e: "x20" to 0x20

or: "20" to 0x20

This will drastically simplify a function to convert the HTML encoded characters to their ASCII equivalent. If I can't do it like this the only other way I can think of is to manually write out each counterpart in a huge switch statement i.e:

Code:

int x = 0;
switch (string) {
   case "20":
   x = 32;
...

^ Which is obviously not valid code but you get the idea :P

Then casting the integer to a character and replacing it in the string.

Thanks!

Originally Posted by tabstop

Why not use %x with *scanf?

Because it's not a string coming from stdin, it's a string being returned from a HTTP socket connection.

Can I still use it?

Originally Posted by tabstop

Well, yes. There is a version of scanf that reads from stdin, a version that reads from any FILE*, and a version that reads from a string, and some other various versions as well. (That's what my * was referencing in the post.)

I figured that * was placed there for a reason Google yields no results. Are you saying using the address of the function for some reason? Mind pointing me in the right direction or a bit of an explanation? Thank you Tabstop

Never mind, sscanf Thanks tabstop.