RewriteRule that will force a trailing slash

Currently I have a folder [contact-us]

mydomain.com/conta开发者_运维百科ct-us/

Im planning to remove this folder and will just add a contact-us.php

mydomain.com/contact-us.php

How can I create a RewriteRule that will map

mydomain.com/contact-us/ -> mydomain.com/contact-us.php

(Note I want to force a trailing slash)

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Use:

RewriteEngine On
RewriteRule ^contact-us$ http://domain.com/contact-us/ [R,L]
RewriteRule ^contact-us/?$ /contact-us.php [NC,QSA,L]

This way is someone type: contact-us or contact-us/ it will go to your contact-us.php

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RewriteRule ^contact_us/$ /contact_us.php [QSA]

I can't remember if you need a / at the start, so if this doesn't work try ^/contact_us/$