.htaccess files not working and how to rename files using htaccess

I am using below script to hide file extension in my website.i got this script from net

Rew开发者_开发百科riteEngine on
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.php -f
RewriteRule ^(.*)$ $1.php

but this script is not working,its showing no error but its not hiding file extension ;can you tell me whats happening in this..i am new to this script..

and can you also tell me how to rename my php and show in url using htaccess(to prevent hacking)

 (eg www.website.com/contact.php to www.website.com/Mycontact)

The provided code should work, if you type in www.site.com/contact do you arrive at www.site.com/contact.php?

To 'rename your php' you will have to make the .htaccess very specific like so:

RewriteRule ^Mycontact$ contact.php

Maybe it is better to do something along these lines:

RewriteRule ^(.*)$ loader.php?p=$1

And then have loader.php contain something like this code:

$pages = array();
$pages['Mycontact'] = 'contact.php';

if(isset($_GET['p']) && isset($pages[$_GET['p']]))
    require $pages[$_GET['p']];
else // redirect to homepage
    header('Location: http://www.site.com/');

Or with a switch

switch($_GET['p']){

    case "Mycontact":
    require 'contact.php';
    break;

    default:
    header('Location: http://www.site.com/');

}