URL Redirectors

Category:Contributions::Applications

I have created a URL Redirecting service using CodeIgniter 1.7.1. If you are interested in the source, let me know and I will post the controllers and models.

The site is called [b]9source[/b]. The URL is [url=http://9src.com]http://9src.com[/url]

It was actually very easy to create. The hardest part was generating the short URL. I had to come up with a way to create a unique identifier, and keep it short. I came up with the idea of just starting the first one at 'a' (url of http://9src.com/a) and then "add" 1 to it each time. URLs would end up looking like this:

-http://9src.com/a -http://9src.com/b -http://9src.com/c -http://9src.com/d ... -http://9src.com/z -http://9src.com/A -http://9src.com/B -http://9src.com/C ... -http://9src.com/Z -http://9src.com/aa -http://9src.com/ab -http://9src.com/ac and so on...

Here is th

Here is the code that makes this happen:

[code] function increase_string($str) { $len = strlen($str); $inced = false;

    for($i = $len - 1; $i >= 0; $i--)
    {
        if($str[$i] != 'Z')
        {
            $str[$i] = $this->increase_letter($str[$i]);
            break;
        }
        else
        {
            $str[$i] = "a";
            if($i == 0)
            {
                $str = "a" . $str;
            }
        }
    }
    return $str;

}
function increase_letter($letter)
{
    //Lowercase: 97-122
    //Uppercase: 65-90
    $ord = ord($letter);
    if($ord == 122)
    {
        $ord = 65;
    }
    else
    {
        $ord++;
    }
    return chr($ord);
}

[/code]

To use it you simply call it like this: [code]$this->increase_string("a");[/code]

It will return "b". Likewise, if you send it "snfiz", it will return "snfiA".