title: Detect if a dropdown list is a multi-select
body: <p>I have a generic dropdown list filler script which populates the <code>select</code> with the options returned from various jquery calls.  It currently is intended for a single selection.  I need to add to it the ability to fill a multi-select, which works as-is, but I don't want to include the initial * Please choose * option.
  I'm looking for either a jQuery or plain Javascript solution.</p>
  
  <pre><code>if (dropdown != null) {
      var regList = document.getElementById(dropdown);
      regList.options.length = 0;
      var opt = document.createElement("option");
  
      // ** if the dropdown is *not* a multiple="multiple", 
      // add the first option as an empty value
  
      opt.text = " -- Select --";
      opt.value = "";
      regList.options.add(opt);
  
      // **
  
      // loop thorugh child nodes and fill dropdown.
      $.each(arg.d, function () {
          opt = document.createElement("option");
          opt.text = this;
          opt.value = this;
          regList.options.add(opt);
      });
      $('.SpinImage').remove();
  }
  </code></pre>