URL segment class

Question

I'm trying to create URL parse class., so i can check URL Segment / part,

Example:

1. http://localhost/myproject/class/method/arg/other (localhost)
2. http://www.myproject.com/class/method/arg/other (live site)
3. http://www.myproject.com/class/method/arg/other?param=value (with get param)

In urls above:

• $url->segment(1) : class
• $url->segment(2) : method

If argument null, it will return the last segment:

• $url->segment() : other

I need suggestions for improvement this class, here is the code:

<?php
class url
{
    private $url;

    public function segment($arg=null)
    {
        if($arg==null)
        {
            $this->url = str_replace(BASEDIR,'',$_SERVER['REQUEST_URI']);

            if(isset($_GET))
            {
                $this->url = explode('?',$this->url);
                $this->url = $this->url[0];
            }

            $this->url = explode('/', trim($this->url, '/'));       


            return end($this->url);
        }
        else
        {
            $this->url = str_replace(BASEDIR,'',$_SERVER['REQUEST_URI']);
            if(isset($_GET))
            {
                $this->url = explode('?',$this->url);
                $this->url = $this->url[0];
            }

            $this->url = explode('/', trim($this->url, '/'));

            array_unshift($this->url, null);

            unset($this->url[0]);

            if(isset($this->url[$arg]))
            {
                return $this->url[$arg];
            }
            else
            {
                return null;
            }
        }
    }
}    
?>

Answer 1

Just a quick note: there is some duplication in the two branches of the first if. You could write the following:

<?php
    public function segment($arg=null)
    {
        $this->url = str_replace(BASEDIR,'',$_SERVER['REQUEST_URI']);
        if(isset($_GET))
        {
            $this->url = explode('?',$this->url);
            $this->url = $this->url[0];
        }
        $this->url = explode('/', trim($this->url, '/'));       


        if($arg==null)
        {
            return end($this->url);
        }
        else
        {
            array_unshift($this->url, null);
            unset($this->url[0]);
            if(isset($this->url[$arg]))
            {
                return $this->url[$arg];
            }
            else
            {
                return null;
            }
        }
    }
}    
?>

Actually, the else keyword is unnecessary since if the $arg == null condition is true the function returns.

    ...
    if($arg==null)
    {
        return end($this->url);
    }

    array_unshift($this->url, null);
    unset($this->url[0]);
    if(isset($this->url[$arg]))
    {
        return $this->url[$arg];
    }
    // else is unnecessary here too
    return null;