title: merge control functions for checkboxes/ selects and inputs into one
body: <p>I've the following functions which enables/ disables a submit button in a form. All three are working fine separately but how merge them into one if it's possbile?</p>
  <p>Now, if i select an option and a checkbox, the button is enabled, but if i deselect an option, the submit button is disabled again, but i want to let him enabled if one checkbox or option is select or one field is filled in.</p>
  <pre><code>$('#order input[type=&quot;text&quot;]').change(function(){
  if(($(this).val().length &gt; 0))
  $('#submit').prop('disabled', false);
  else
  $('#submit').prop('disabled', true);
  });
              
  $('#order :checkbox').change(function(){
              if($(this).not('.others').is(':checked'))
  $('#submit').prop('disabled', false);
  else
          $('#submit').prop('disabled',true);
      
      });
  $('#order select').not('#sel_option_img').change(function(){
              if($(this).val() != '')
  $('#submit').prop('disabled', false);
  else
      $('#submit').prop('disabled',true);
      
      });
  
  });
  </code></pre>
  <p>Sorry for my english, maybe not perfect.</p>
  <p>Thanks in advance for helping.</p>
  <p><strong>EDIT</strong></p>
  <p>Link to the fiddle for better understanding:</p>
  <p><a href="http://jsfiddle.net/zVS3t/4/" rel="nofollow noreferrer">http://jsfiddle.net/zVS3t/4/</a></p>