.htaccess - use htaccess file to prevent link to specific external site? -

i have social network using popular php framework. competition trying spam site links site. there way use htaccess prevent links leading site? have www.his_domain.com clicks lead google or right home page?

you can use rewritecond , rewriterule create rules

rewritecond %{request_uri} his_domain.com

rewriterule google.com

but preventing user navigating external sites many not work badzen said. can try preventing spam instead