Ajax Username Check - Using JQuery!

What happens?

The embedded javascript picks up the onblur event of the input field with id username.

It then sends a post request to check.php which checks the csv for the filename and returns the result.

The embedded javascript then updates the span element with id usernameResult.

The Code!

index.html - check source

jquery.js - a super javascript utility! check out jQuery

data.csv - CSV file that contains the user information

"username","first_name","last_name","password"
"john","John","Doe","123456"
"martin","Martin","Petrov","111111"

check.php

<?
$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>';
}
?>