Question

I have a form that inputs url

dynamically, the user may input

www.stack.com  or
www.stack.com/overflow  or
http://www.stack.com  or
http://www.stack.com/overflow

how can I prevent to insert the duplicate entry to my database?

I’ve tried these

$url = (input url)

$search = str_replace("http://www.", "", $url);
$search = str_replace("http://", "", $url);
$search = str_replace("www.", "", $url);
$search = str_replace("/", "", $url);

at the last $search, I wanted to remove all the following character after “/” including “/”
what does follow?

Answer 1

For some who will stuck with the same question and drop here, here’s the complete code for this

if((strpos($url, 'http://')  !== false) || (strpos($url, 'https://')  !== false)) 
{   $host = parse_url($url, PHP_URL_HOST); 
    if (strpos($url, 'www.') !== false)
        $host = str_replace('www.', '', $host);
    if (strpos($host, '/') !== false)
    {   $str = explode("/", $host);
        $host = $str[0];
    }
}

else if (strpos($url, 'www.') !== false)
{   $host = str_replace('www.', '', $url);
    if (strpos($host, '/') !== false)
    {   $str = explode("/", $host);
        $host = $str[0];
    }

}
else if (strpos($url, '/') !== false)
    {   $str = explode("/", $url);
        $host = $str[0];
    }

else $host = $url;