.htaccess if contains dash redirect

[PaPPy]

i have tried htaccess creators, but nothing is working

i want to make it if the url contains a dash (last character)
ex: http://site.com/a3s-
to redirect to a file preview.php?id=a3s

[thewebhostingdi]

Kindly refer to below mentioned URL which might helps you to write the htaccess code in your .htaccess file.

http://corz.org/serv/tricks/htaccess2.php

[PaPPy]

<IfModule mod_rewrite.c>
   RewriteEngine on
   RewriteOptions MaxRedirects=1
   RewriteBase /
   RewriteCond %{REQUEST_FILENAME} !-f
   RewriteCond %{REQUEST_FILENAME} !-d
   RewriteCond %{REQUEST_FILENAME} !-l
   RewriteRule ^([a-zA-Z0-9_-]+)$ redirect.php?alias=$1 [L]
</IfModule>

what that is the code that is being used for the url shrink script

i dont know if i need to add a separate module to say if that variable $1 contains a dash to redirect to preview.php?alias=$1
and if it contants a-zA-Z0-9 to goto redirect.php?alais=1