How do I add 'nofollow' link in java script

Question

I tried in this way but it is not working:

Java Script:
<script type="text/javascript">

  function DoNav(theUrl)
  {
  document.location.href = theUrl;
  }
  </script>
Php code:
echo " onclick=\"DoNav('https://www.example.com/profile.php?id={$profile_id}'rel='nofollow');\">\n"; 

Answer 1

nofollow concerns a classic link, not for a link opened on JS. It's for search engine robots.

// Will indicate a robot that it does not have to follow this link
<a href="http://www.link.com" rel="nofollow"></a> 

// If your action is JS opened you don't care to set nofollow, robots won't go on it.
<a href="#" onclick="window.open('http://www.link.com');"></a>

If you just want to prevent robot from accessing a particular adress on your website, you should use robots.txt : http://robots-txt.com/

If you just don't want google to access your particular page profile.php, You can ad this in robots.txt :

User-agent: Googlebot
Disallow: profile.php

And you can use classic links instead of JS ones, and add nofollow too :

<a href="./profile.php?id={$profile_id}" rel="nofollow">...</a>

You don't need to open it with JS