redirect ex-ample.com/asdf to example.com/asdf

I want to redirect all requests from ex-ample.com to example.com. The url structure should remain the same, I only want to "replac开发者_开发百科e" the "-" in domain...

http://www.ex-ample.com/asdf123
redirects to:
http://www.example.com/asdf123

thanks!

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If it’s just a single hyphen:

RewriteCond %{HTTP_HOST} ^([^-]+)-([^-]+)$
RewriteRule ^ http://%1%2%{REQUEST_URI} [L,R]