title: Check for whitespace at beginning of string
body: <p>I need to use <code>preg_match</code> to check that only a-z0-9. is used (including full stop(.)). I don't want to replace anything. My problem is that it doesn't notice white space at beginning of a string.</p>
  
  <p>Also, if anyone knows how to check there is no two full stops in a row, I would be very grateful.</p>
  
  <p>What I have so far:</p>
  
  <pre><code>("/[^a-z0-9.]+$/",$request)
  </code></pre>
  
  <p>Thanks !</p>