.htaccess - htaccess - rewriterule help needed -

i having problem rewrite rules. have urls variables this: localhost/mysite/user.php?u=username. want convert them this: localhost/mysite/user/username/

this have tried

rewriterule  ^user/([a-za-z0-9-]+)/?$    /mysite/user.php?u=$1    [nc,l]     # handle user page requests 

but not working :(

/mysite/user.php in htdocs folder (because in local environment)

if somehow url opened localhost/user.php?u=username should redirect or change localhost/user/username/, possible?

you can use code in /mysite/.htaccess file:

options -multiviews rewriteengine on rewritebase /mysite/  rewritecond %{the_request} /user\.php\?u=([^\s&]+) [nc] rewriterule ^ user/%1/? [r=302,l,ne]  rewritecond %{request_filename} !-f rewritecond %{the_request} \s/+(.*?)[^/][?\s] rewriterule [^/]$ %{request_uri}/ [l,r=301]  rewriterule ^user/([^/.]+)/$ user.php?u=$1 [l,qsa,nc]