title: Remove specific characters from a string in Javascript
body: <p>I am creating a form to lookup the details of a support request in our call logging system.</p>
  <p>Call references are assigned a number like <code>F0123456</code> which is what the user would enter, but the record in the database would be <code>123456</code>. I have the following code for collecting the data from the form before submitting it with <code>jQuery</code> ajax.</p>
  <p>How would I strip out the leading <code>F0</code> from the string if it exists?</p>
  <pre><code>$('#submit').click(function () {        
              
  var rnum = $('input[name=rnum]');
  var uname = $('input[name=uname]');
  
  var url = 'rnum=' + rnum.val() + '&amp;uname=' + uname.val();
  </code></pre>