title: Check if window opener is on the same domain using jQuery
body: <p>I have a child page that can be opened either from its parent page on the same domain (mydomain.com) or from other pages on other domains (as a link) such as facebook, email link etc. How can I check whether or not the child window was opened by the parent window on mydomain.com? The reason is that I want to run a jQuery code only if the window opener exists and it is on mydomain.com. Something like the following code:</p>
  
  <pre><code>if (window.opener &amp;&amp; /*window opener is on mydomain.com*/ )
     { 
     alert('Window opener exists and on my domain');
     }
  </code></pre>