Javascript: Octal to ASCII

Gareth Heyes posted a fun little challenge and I couldn’t help but attack it. It took me longer than I thought. Not to be a spoiler, but at some point you have to convert octals to ASCII values. Now, I have done decimal to ASCII, binary to ASCII, and even hex to ASCII, but never octal to ASCII. Searching around, I found everyone seemed to use PHP, ASP, or some sort of “higher” level programming.

I found some really old code on some google cache, which I lost the url to, and it seemed to work. By working, I mean, the idea was right, the code wasn’t. After fooling around with it for a bit, I got something like the following.

String.prototype.octToAscii = function()
{
  var temp = '', result = '', input = this + '%';
  for(i = 0; i < input.length; i++)
  {
    if (input.charAt(i) != '%')
    {
      temp += input.charAt(i);
    }
    else if (temp != '')
    {
      var running = 0;
      var notMatchedYet = true;
      for(j = 0, k = temp.length - 1; k >= 0; j++, k--)
      {
        if( (temp.match("\\n")) && (notMatchedYet) )
        {
          k--;
          notMatchedYet = false;
        }
        partial = temp.charAt(j) * Math.pow(8, k);
        running += partial;
      }
      result += String.fromCharCode(running);
      temp = '';
    }
  }
  return result.replace(/%40%/g, "%40<br />%")
};

3 Responses to “Javascript: Octal to ASCII”

Gareth Heyes | October 11th, 2007 | 3:54 am

Nice work! I’m glad you looked for a javascript solution that was my intention to have a simple challenge which demonstrated some of the techniques on my blog.
Mind Mining Medium » Solution to The Spanner’s “A bit of fun” challenge | October 25th, 2007 | 6:59 pm

[...] while back, The Spanner’s very own Gareth Heyes posted a decent challenge. As I stated in a previous posting I took on the challenge. It didn’t take as long as I thought it would, but it was still [...]
Emil | June 9th, 2008 | 9:03 am

How do i use it?

Mind Mining Medium

3 Responses to “Javascript: Octal to ASCII”

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