hex to decimal conversion !

hello !

how can i convert a hex to decimal in VC++?
any function available

use atoi

Hi!!

There is no direct function(as far as i know) to convert a hex number to decimal, but it is very easy to write to simple function for that.

Regards
Shaunak

Conversion from hex to decimal... do you mean from hexadecimal representation to decimal representation or from hexadecimal representation to a real number?

Case b: use strtoi

Case a:

Code:

---

#include <string>
#include <sstream>
#include <iomanip>
using std::string;
using std::ostringstream;
using std::istringstream;
using std::hex;

void hextodecimal(const string &in, const string &out)
{
  int temp;
  istringstream iss(in);
  iss >> hex >> temp;
  ostringstream oss;
  oss << temp;
  out = oss.str();
}

---

should work.

Hi CB,
The code above tries to modify something that's const.

Code:

---

void hextodecimal(const string &in, const string &out)

---

so that should be

Code:

---

void hextodecimal(const string &in, string &out)

---

or if you want the function to return a value (which I think is more logical in this case)

Code:

---

string hextodecimal(const string &in)
{
  int temp;
  istringstream iss(in);
  iss >> hex >> temp;
  ostringstream oss;
  oss << temp;
  return oss.str();
}

---

thanks !
can we write hex to decimal conversion code in C ???

pls tell me... its sor of very urgent, my entire project is held up due to this

awaiting for a prompt reply

shruti !!!

atoi what was i thinking :o its strtol as CB said, here's an example of how to use it:
http://www.cplusplus.com/ref/cstdlib/strtol.html

Here's another alternate way.

Code:

---

#include<stdio.h>

void HexToDec(const char *HexStr, int *DecNum)
{
  sscanf(HexStr,"%x",DecNum); 
  return;
}

---

You can take it out of the function if you want.

Quote:

---

Originally posted by Jop
Hi CB,
The code above tries to modify something that's const.

Code:

---

void hextodecimal(const string &in, const string &out)

---

so that should be

Code:

---

void hextodecimal(const string &in, string &out)

---

or if you want the function to return a value (which I think is more logical in this case)

Code:

---

string hextodecimal(const string &in)
{
  int temp;
  istringstream iss(in);
  iss >> hex >> temp;
  ostringstream oss;
  oss << temp;
  return oss.str();
}

---

---

Oops, right. But I don't want to return a string object, that involves too much memory copying IMO. So the non-const reference was what I wanted.