exact syntax of RewriteRule

Do I need a slash before or after the /somefolder/(.*) below? I want to redirect everything coming into a folder to another website address. Do I need the RewriteCond in here somewhere also?

Options +FollowSymLinks
RewriteEngine on

开发者_C百科RewriteRule somefolder(.*) http://www.differentsite.com$1 [R=301,L]

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You don't need a / at the beginning, but a caret ^ will match http://whatever.com/ including the trailing /.