title: Codeigniter: dropdown validation set_rules
body: <p>may i know how do i ensure that the user have selected, Dr, Mr, Ms, Mdm and when they submit the form if the salutation is given as blank it will return an error message for the set_rules().</p>
  
  <p>Code:</p>
  
  <pre><code>echo "&lt;p&gt;Salutation: ";
      $salutationOptions = array(
                    ''  =&gt; '',
                    'Dr'  =&gt; 'Dr',
                    'Mr'    =&gt; 'Mr',
                    'Ms'   =&gt; 'Ms',
                    'Mdm' =&gt; 'Mdm',
                  );
      echo form_dropdown('salutation', $salutationOptions, '');
      echo "&lt;/p&gt;";
  </code></pre>