Railsでphpのstrip_tagsみたいなことをしたかったらstrip_tagsよりsanitize strip_tags('<b class="bb" id="bbb" >Bold</b><a>Anchor</a>') => BoldAnchor sanitize( '<b class="bb" id="bbb" >Bold</b><a>Anchor</a>', :tags => ["b"] ) => <b class="bb">Bold</b>Anchor sanitize( '<b class="bb" id="bbb" >Bold</b><a>Anchor</a>', :tags => ["b"], :attributes => ["id","class"] ) => <b class="bb" id="bbb">Bold</b>Anchor