User registration validation

[userjosh]

Feel free to move this post if it is in the incorrect category. I was using a validation method for usernames on my website but I would like to make some improvements on it. You typed in your name and it would search and pop-up whether it was available or not. I am looking for a method similar to the one used on this website and many others that checks when the field loses focus. The php code and easiest example I have found is here: http://shawngo.com/wp/blog/gafyd/index.html

 

$username = $_POST['username']; // get the username
$username = trim(htmlentities($username)); // strip some crap out of it
$file = '/home/js4hire/public_html/gafyd/data.csv'; // Here's the file. Notice the full path.

echo check_username($file,$username); // call the check_username function and echo the results.

function check_username($file_in,$username){
$username=strtolower($username);
$file = file($file_in);
foreach ($file as $line_num => $line) {
	$line = explode(',',$line);
	$user = trim(str_replace('"','',$line[0]));
	if($username == strtolower($user)){
		return '<span style="color:#f00">Username Unavailable</span>';
	}
}
return '<span style="color:#0c0">Username Available</span>';
}

 

That example uses a flat file CSV, but I would like to use my MySQL database instead. I have included a snippet from my previous  that I believe would tie into this, I'm just not sure how exactly:

 

require_once dirname(__FILE__).'/../includes/common.inc.php';
require_once dirname(__FILE__).'/../includes/user_functions.inc.php';

$output='';
if (!empty($_POST['user'])) {
$user=sanitize_and_format($_POST['user'],TYPE_STRING,$__field2format[FIELD_TEXTFIELD]);
if (get_userid_by_user($user) || $user=='guest') {
	$output=1;
}
}
echo $output;

 

That common.inc.php calls for the database connection in session.inc.php:

$josh_dblink=db_connect(_DBHOST_,_DBUSER_,_DBPASS_,_DBNAME_);
if (!defined('NO_SESSION')) {
require _BASEPATH_.'/includes/sessions.inc.php';
}

 

I don't want to have to call the db connection again in that file but I need to get the relevant information and pass it through the php. Any help would be appreciated!

[dink87522]

Don't  a lot of sites use AJAX to do that?

[userjosh]

There are several ways I could answer that question... But I'll be nice and say, yes. There are a lot of sites that use ajax. Thank you for that observation. Now, anyone that can help with the PHP question I posted?

[Rifts]

you can not do this purely with php. I would recommend php + jquery

here is a very simple very easy to follow youtube video on how to do it