title: Regex: allow everything but some selected characters
body: <p>I would like to validate a textarea and I just don't get regex (It took me the day and a bunch of tutorials to figure it out).</p>
  
  <p>Basically I would like to be able to allow everything (line breaks and chariots included), but the characters that could be malicious( those which would lead to a security breach).
  As there are very few characters that are not allowed, I assume that it would make more sense to create a black list than a white one.</p>
  
  <p>My question is: what is the standard "everything but" in Regex?</p>
  
  <p>I'm using javascript and jquery.</p>
  
  <p>I tried this but it doesn't work (it's awful, I know..):</p>
  
  <pre><code>var messageReg = /^[a-zA-Z0-9éèêëùüàâöïç\"\/\%\(\).'?!,@$#§-_ \n\r]+$/;
  </code></pre>
  
  <p>Thank you.</p>